I am super excited about this episode.
Speaker:We have a networking expert coming on and we talk about what to do in your network,
Speaker:when you get a ransomware attack, I bet you've been wanting to know that answer.
Speaker:So stay tuned.
W. Curtis Preston:Hi and welcome to Backup Central's Restore All podcast.
W. Curtis Preston:I'm your host, W.
W. Curtis Preston:Curtis Preston, aka a Mr.
W. Curtis Preston:Backup and have with me possibly my Pex consultant Prasanna Malaiyandi.
W. Curtis Preston:How's it going?
W. Curtis Preston:Prasanna,
Prasanna Malaiyandi:am.
Prasanna Malaiyandi:I'm good Curtis.
Prasanna Malaiyandi:And just for people that's p e x, not P E C K S.
W. Curtis Preston:Yeah, this is the piping, the, uh, the modern
W. Curtis Preston:piping alternative to copper, which I think is far superior.
W. Curtis Preston:And, uh, You know what?
W. Curtis Preston:Just, just for those that are watching this on on video, which is only a
W. Curtis Preston:handful of you, but I'm gonna tilt my camera up and this is what my office
W. Curtis Preston:looks like right now because I got yet another pinhole leak in my, um, second
W. Curtis Preston:story bathroom water supply, which happens to be right above my office.
W. Curtis Preston:And yesterday I was just sitting here at my desk and I get this
W. Curtis Preston:drip drip on my face and I'm like,
Prasanna Malaiyandi:you're like, am I sweating profusely?
W. Curtis Preston:Yeah.
W. Curtis Preston:And the pipe, the pipe is actually over there.
W. Curtis Preston:The, the, the joint that's leaking, it's actually over there, but you know,
W. Curtis Preston:the water finds its way, you know,
W. Curtis Preston:along a drywall seam and then it just sort of drips
W. Curtis Preston:down onto my face.
Prasanna Malaiyandi:you know what though, Curtis, I have to say
Prasanna Malaiyandi:congratulations on finally finishing your other project, which we should
Prasanna Malaiyandi:tell our
W. Curtis Preston:my other pro.
W. Curtis Preston:Yeah.
W. Curtis Preston:Yeah.
W. Curtis Preston:For those who have been following along my other project is, is, I
W. Curtis Preston:mean, it, it's still, you know, at this point it's 98% done.
W. Curtis Preston:But, you know, I have put the, the stair, you know, the, the,
W. Curtis Preston:the flooring on the stairs.
W. Curtis Preston:Um, it looks really good.
W. Curtis Preston:Uh, it looks way better than the ceiling in this room, I will say that.
W. Curtis Preston:Um, and now there's the official first mess on the new floor
W. Curtis Preston:. There's just, as I
Prasanna Malaiyandi:At some point it's gonna happen, you know?
W. Curtis Preston:yeah.
W. Curtis Preston:Well, apparently that some point is today.
W. Curtis Preston:Uh, but yeah, so the plumber, who is a good guy, uh, he's been here before,
W. Curtis Preston:um, he, um, he's talking to me about, he knows a guy that does, uh, PEX repiping
W. Curtis Preston:so, we'll,
Prasanna Malaiyandi:Our listeners will learn all about water piping
Prasanna Malaiyandi:soon in the next few episodes as we go
W. Curtis Preston:More, more than you ever wanted to know.
W. Curtis Preston:Uh, and by the way, I did check they can go through the attic.
W. Curtis Preston:So, um, that is a, that is a real possibility for the, um, and, um, yeah,
W. Curtis Preston:so anyway, um, and I just realized that, uh, my son-in-law is home today.
W. Curtis Preston:He's not normally home.
W. Curtis Preston:I just heard him making noise.
W. Curtis Preston:I hope he gets his bath out of the way before the plumber gets here.
W. Curtis Preston:I didn't, I didn't warn him.
W. Curtis Preston:Uh, I actually hear, I hear a bath going on right now, . So,
W. Curtis Preston:so that answer's that question.
W. Curtis Preston:Way too much information going on at depress pressing
W. Curtis Preston:household.
W. Curtis Preston:Well, listen.
Prasanna Malaiyandi:okay.
W. Curtis Preston:Yeah, we wanna bring on our guest.
W. Curtis Preston:Uh, he is both, I would say, a friend of the pod.
W. Curtis Preston:He's also been an enemy of the pod at once.
W. Curtis Preston:You may recall that we had an episode where basically we just argued
W. Curtis Preston:with Tom without his per, without him being here to defend himself.
W. Curtis Preston:Um, that was over a blog post that he said, uh, something about, uh, backup
W. Curtis Preston:people reporting to security people.
W. Curtis Preston:And, uh, I
W. Curtis Preston:think I had an issue with that or something.
W. Curtis Preston:Tom has been in the industry about 20 years and he is an
W. Curtis Preston:event lead over at Gestalt.
W. Curtis Preston:It the, uh, what would you call it?
W. Curtis Preston:The makers of the Tech Field Day series, which, uh, uh, my
W. Curtis Preston:employer has used quite a bit.
W. Curtis Preston:And, um, uh, we're glad to have him on the podcast.
W. Curtis Preston:Welcome, Tom Hollingsworth.
Tom Hollingsworth:Well, thank you for having me on Curtis.
Tom Hollingsworth:It was, uh, it was fascinating to listen to an episode where I was, I was arguing
Tom Hollingsworth:with somebody and it wasn't even here.
Tom Hollingsworth:But, uh, I, I, I love, I love listening to you guys, and I've learned quite a bit.
Tom Hollingsworth:In fact, uh, the very first time that Curtis and I ever met at Tech Field Day
Tom Hollingsworth:back in 2011, he was teaching me about data de-duplication, and I was trying to
Tom Hollingsworth:convince him that IP V6 was important.
Tom Hollingsworth:And I can tell you which one of those things panned out a lot better than the.
W. Curtis Preston:Uh, well, you know, is it, is that the thing where
W. Curtis Preston:you do the nat behind the thing?
W. Curtis Preston:That's what I recall really learning from you was that you gotta do
Tom Hollingsworth:if you want me to come crashing through your roof
Tom Hollingsworth:like the Kool-Aid man, just keep
Tom Hollingsworth:it up my.
W. Curtis Preston:Yeah.
W. Curtis Preston:Yeah.
W. Curtis Preston:I wanted to bring on somebody that actually understood networking
W. Curtis Preston:far better than me, right?
W. Curtis Preston:Which, which is basically many people in the world.
W. Curtis Preston:With ransomware attacks.
W. Curtis Preston:One of the things that we talk about is once you've, um, you
W. Curtis Preston:know, figured out that you actually have a ransomware attack, you,
W. Curtis Preston:you want to isolate the network.
W. Curtis Preston:And there there's a discussion, you know, I've been talking with with CISOs lately
W. Curtis Preston:and, and, and what, what appears to be the reality is that that few environments
W. Curtis Preston:actually do the, the actual full.
W. Curtis Preston:Like we just we're just shutting everything off.
W. Curtis Preston:Right.
Prasanna Malaiyandi:Go grab the cable, pull it out quick, quick,
W. Curtis Preston:
Speaker:They're actually, I know.
W. Curtis Preston:
Speaker:Tom, did you ever watch, uh, alias when it was on
Tom Hollingsworth:I've seen a couple of
W. Curtis Preston:and.
W. Curtis Preston:Okay, well there's an episode in there when they were having a cyber
W. Curtis Preston:attack and the, uh, what's his name?
W. Curtis Preston:Um, uh, Marshall Flank man comes running into the data center and he just literally
W. Curtis Preston:starts flipping, flipping power switches.
W. Curtis Preston:He's like, they're downloading all the files off the server and he down.
W. Curtis Preston:He just flips all the power switches off.
W. Curtis Preston:And so, you know, on one end there is the complete.
W. Curtis Preston:like networking, shutdown, like literally both internal and external, right?
W. Curtis Preston:Um, because, you know, once the, once the ransomware is inside, it's gonna try to
W. Curtis Preston:crawl around and, and make things worse.
W. Curtis Preston:So that's one way.
W. Curtis Preston:And then there are, you know, and, and then there's the, those that go, well,
W. Curtis Preston:well, I'm just going to turn it off, or I'm gonna unplug the cable at the
W. Curtis Preston:one server or the three servers that appear to be infected and I'm not gonna
W. Curtis Preston:worry about the rest of the network.
W. Curtis Preston:And somewhere in the, between those two extremes is what everybody else does.
Prasanna Malaiyandi:And maybe we should also talk about basics
Prasanna Malaiyandi:of networking before we jump into this to talk about the detail.
Prasanna Malaiyandi:Because just
W. Curtis Preston:Go ahead.
W. Curtis Preston:Go ahead.
W. Curtis Preston:Prasanna,
W. Curtis Preston:what, what do you think we should be talking about first?
Prasanna Malaiyandi:no, I think it's sort of, because what you just
Prasanna Malaiyandi:mentioned, Curtis, like everyone might think, oh, all computers
Prasanna Malaiyandi:are plugged into the same network.
Prasanna Malaiyandi:Right?
Prasanna Malaiyandi:I think it's important to talk about some of the best practices from networking,
Prasanna Malaiyandi:Tom, if you could, about sort of network isolation, BLANs, other things like that.
Prasanna Malaiyandi:Before we get into sort of the other side of things,
W. Curtis Preston:Yeah, so please explain all networking technology, period before
Tom Hollingsworth:the good news.
Tom Hollingsworth:,you've already talked a little bit about it because it's just
Tom Hollingsworth:a series of tubes, pipes, if you will, that we send things through.
Tom Hollingsworth:Uh, now the, the, the important thing to realize when you're trying to think
Tom Hollingsworth:about how ransomware propagates through a network is to realize that, um, the
Tom Hollingsworth:way that networks have traditionally been built is we have this perimeter
Tom Hollingsworth:on the outside, you know, it's probably bounded by firewalls and a bunch of
Tom Hollingsworth:other stuff, and it looks really, really imposing on the castle walls,
Tom Hollingsworth:but inside of the network, it's a whole lot easier to get around.
Tom Hollingsworth:And that's just due to the nature of the way that that networks operate.
Tom Hollingsworth:I mean, ethernet is effectively like trying to shout out somebody's order
Tom Hollingsworth:number at a fast food restaurant and hoping that you get the right one.
Tom Hollingsworth:Everybody's gonna hear the message, but if it's not meant for you,
Tom Hollingsworth:we're just gonna ignore it.
Tom Hollingsworth:But the problem is, is that that allows you to propagate a lot of information
Tom Hollingsworth:very quickly, and that's what ransomware is trying to take, uh, advantage of
Tom Hollingsworth:whenever it's, it's trying to, uh, do almost like, you know, reconnaissance
Tom Hollingsworth:lateral movement in the network.
Tom Hollingsworth:So I'm, I'm looking for a whole bunch of, um, , potentially vulnerable servers
Tom Hollingsworth:going all the way back, you know, to the beginning of my professional IT career,
Tom Hollingsworth:I was actually working on a help desk, uh, when the S SQL slammer worm came out.
Tom Hollingsworth:And boy, you'd be surprised how many people had that port open to the internet,
Tom Hollingsworth:uh, because everything shut down.
Tom Hollingsworth:And it was really weird to see that.
Tom Hollingsworth:And you're like, well, you know, at the time I'm, I'm kind of
Tom Hollingsworth:freshly minted in my career.
Tom Hollingsworth:And I'm like, well, how could that happen?
Tom Hollingsworth:And, and now all these years later, I look at it and go, oh my God,
Tom Hollingsworth:these people were stupid because you're not supposed to do that.
Tom Hollingsworth:But that's one of the things that people want to take advantage of because the,
Tom Hollingsworth:the systems want to talk to each other.
Tom Hollingsworth:They want to be able to exchange information.
Tom Hollingsworth:That's the purpose of a network.
Tom Hollingsworth:You actually have to do extra work to prevent them from talking to each other.
W. Curtis Preston:Right.
W. Curtis Preston:Yeah.
W. Curtis Preston:I think that's, you know, I, I, and the, the number of times I went in and out
W. Curtis Preston:of data centers, uh, over the years, I remember only one, uh, where they had
W. Curtis Preston:very solid internal firewalls, basically.
W. Curtis Preston:Right.
W. Curtis Preston:That, that it was very difficult to do, to traverse laterally
W. Curtis Preston:within the organization.
W. Curtis Preston:And that was actually Intuit, uh, right.
W. Curtis Preston:And, and it's because of what they felt they had.
W. Curtis Preston:Right.
W. Curtis Preston:They had all of this very sensitive personal data, thanks to their, you know,
W. Curtis Preston:they, they had QuickBooks, they have TurboTax, they have all of that stuff.
W. Curtis Preston:And so they had to basically firewall off systems between each other to
W. Curtis Preston:prevent that lateral movement that you're right by design in most networks, you
W. Curtis Preston:buy a switch, you buy, well, a bunch of switches, you plug everything in.
W. Curtis Preston:And everything talk, everything can talk to everything.
W. Curtis Preston:Um, and unless you do something to prevent it, a lot of those ports that
W. Curtis Preston:you talked about, right, just like the SQL, uh, issue, a lot of those
W. Curtis Preston:ports are visible to the internet.
W. Curtis Preston:Right.
W. Curtis Preston:I, I think a, another one would be a, a vCenter Right.
W. Curtis Preston:And Hyper V, the, that, those ports being visible to the internet, I suppose
W. Curtis Preston:you hear about that a lot as well.
Tom Hollingsworth:Yeah.
Tom Hollingsworth:I usually do.
Tom Hollingsworth:Whenever there's some kind of, uh, a vulnerability that comes out and
Tom Hollingsworth:everyone's like, I hope you don't have these exposed to the internet, and
Tom Hollingsworth:you can literally hear the scrabbling as people run into their keyboards
Tom Hollingsworth:to figure out if that's the case.
Tom Hollingsworth:But, you know, as,
Tom Hollingsworth:as Prasanna mentioned, I mean, we have ways to kind of like segment
Tom Hollingsworth:networks away from each other.
Tom Hollingsworth:And it's funny that you bring up that, that Intuit had kind of a, a rigorous
Tom Hollingsworth:internal firewall structure because in my experience, um, companies or organizations
Tom Hollingsworth:that are very, uh, heavily regulat.
Tom Hollingsworth:Have much more strict internal structure.
Tom Hollingsworth:And the reason for that is because they need the ability to say
Tom Hollingsworth:for a fact, Curtis cannot see anything on this network because he
Tom Hollingsworth:hasn't been authorized to see it.
Tom Hollingsworth:Now, you can do that through software constructs.
Tom Hollingsworth:I mean, VLANs, virtual local area networks are kind of the, the most common
Tom Hollingsworth:way to do it, where we, we effectively divide some, uh, uh, partition on the
Tom Hollingsworth:switch and we say, this port belongs to this vlan, so it can only talk to
Tom Hollingsworth:other ports that are on that vlan.
Tom Hollingsworth:Uh, but that's not even good enough for some organizations.
Tom Hollingsworth:And, and the, the one that everybody always thinks of is Mission Impossible,
Tom Hollingsworth:the Tom Cruise movie with the, the machine that's in a vault that's
Tom Hollingsworth:not connected to anything else.
Tom Hollingsworth:We would call that an air gap system.
Tom Hollingsworth:Or you can have an air gap network a lot of times things like, um, HVAC or
Tom Hollingsworth:management systems are air gap from the rest of the network because they
Tom Hollingsworth:have different controls and different needs, but I also don't trust those
Tom Hollingsworth:people to, um, secure their stuff.
Tom Hollingsworth:So I'm gonna build a wall in front of that air gap or just completely
Tom Hollingsworth:isolate it, uh, itself so that I don't have to worry about securing it.
Tom Hollingsworth:And if, uh, you, you say hvac, you say things like, you know, uh, um,
Tom Hollingsworth:environmental control systems and any security people listening to this
Tom Hollingsworth:podcast are immediately thinking, man, those are back doors that I
Tom Hollingsworth:can use to get into the system.
Tom Hollingsworth:Because no matter what, they're still gonna have to be connected
Tom Hollingsworth:to the network somehow.
Tom Hollingsworth:And that just increases your, um, you know, your threat profile.
W. Curtis Preston:Right.
Prasanna Malaiyandi:Yeah, it's interesting because I think most people
Prasanna Malaiyandi:who think about home networks, right?
Prasanna Malaiyandi:Everything's typically flat in a home, right?
Prasanna Malaiyandi:Everything can talk to everything, every single iot device out there, right?
Prasanna Malaiyandi:And they're not always thinking about, Hey, I got this smart light bulb.
Prasanna Malaiyandi:Isn't it great?
Prasanna Malaiyandi:Isn't it awesome?
Prasanna Malaiyandi:And then realizing that's on my network, everything is now exposed and could
Prasanna Malaiyandi:be potentially exposed if there's a security issue with that single device,
Tom Hollingsworth:Those devices are, you know, they obviously have an IP address,
Tom Hollingsworth:they have some kind of a control system.
Tom Hollingsworth:You would hope that most of them have some kind of a security function that
Tom Hollingsworth:allows them to, to securely communicate back to whatever controls them.
Tom Hollingsworth:But multiply that by a factor of 10 for all of the devices that could be
Tom Hollingsworth:on your average enterprise network.
Tom Hollingsworth:And when you start saying things like, you know, access controls for those devices,
Tom Hollingsworth:or port security like network engineering and, and operations folks, like, they
Tom Hollingsworth:just start breaking out into hives.
Tom Hollingsworth:because like the, the, just the amount of work that it takes to create that
Tom Hollingsworth:level of security is its own monster.
Tom Hollingsworth:I mean, anyone who's ever deployed a technology like 8 0 2 0.1 x, which
Tom Hollingsworth:is effectively, I am only gonna allow authorized devices to be plugged into
Tom Hollingsworth:this port, knows that like there's this whole enrollment process and
Tom Hollingsworth:are you on the authorized users list?
Tom Hollingsworth:And what happens if you're using a different device today?
Tom Hollingsworth:And it's just, it's maddening and it, it drives people to insane to the
Tom Hollingsworth:point where, and that's the normal people who know what they're doing.
Tom Hollingsworth:Could you imagine an executive plugging their laptop into a network port one
Tom Hollingsworth:day and going, this doesn't work.
Tom Hollingsworth:And you tell 'em, oh, it's doing that on purpose because we
Tom Hollingsworth:want to keep everything secure.
Tom Hollingsworth:What do you think is gonna happen?
Tom Hollingsworth:The executive's probably gonna look at you and go, I don't care.
Tom Hollingsworth:Make
Prasanna Malaiyandi:Turn it off.
Prasanna Malaiyandi:Exactly.
Prasanna Malaiyandi:. We don't need that.
Tom Hollingsworth:It's getting
Tom Hollingsworth:in my way.
Prasanna Malaiyandi:Yeah,
W. Curtis Preston:Yeah.
W. Curtis Preston:Well, I know that when we, when we had, um, you know, we had a, a, a security
W. Curtis Preston:person on and they had a list of things that they wanted people to do that they
W. Curtis Preston:felt were common sense, that were, um, ways to prevent basically, sort of,
W. Curtis Preston:I, I think the proper thing today when we talk about ransomware is to just
W. Curtis Preston:assume something in your, in your world is going to get ransomware, right?
W. Curtis Preston:It's just, it is, I think it's just impossible to, to,
W. Curtis Preston:to stop it 100% of the time.
W. Curtis Preston:So just assume that's going to happen.
W. Curtis Preston:So then there's all about.
W. Curtis Preston:How to prevent it from activating itself, from talking to the command and control
W. Curtis Preston:servers and also the lateral movement.
W. Curtis Preston:Right?
W. Curtis Preston:So he
Prasanna Malaiyandi:reducing the black
W. Curtis Preston:
Speaker:lateral movement, right?
W. Curtis Preston:
Speaker:So what's that?
Prasanna Malaiyandi:Limiting the blast
W. Curtis Preston:radius.
W. Curtis Preston:So, so Tom, what, what kinds of things besides VLANs?
W. Curtis Preston:Because even VLANs, you know, we have the, we have the VLAN
W. Curtis Preston:for this and the VLAN for that.
W. Curtis Preston:Still all the servers within that VLAN can talk to each other.
W. Curtis Preston:What else can companies do, uh, with modern networking equipment to prevent
W. Curtis Preston:lateral movement or to basically prevent it from everything and then, and then, uh,
W. Curtis Preston:selectively allow it for certain servers.
Tom Hollingsworth:Well, the first thing you have to do is you have to
Tom Hollingsworth:realize that a completely flat network.
Tom Hollingsworth:Is not a stable network.
Tom Hollingsworth:I mean, there is a limit to the amount of chatter that a network can tolerate
Tom Hollingsworth:before it starts running into problems.
Tom Hollingsworth:Um, ethernet is not a, uh, a medium that allows for a large number of hosts because
Tom Hollingsworth:eventually they're gonna, it, you know, it's like recording a podcast eventually
Tom Hollingsworth:with too many guests on the podcast.
Tom Hollingsworth:You're all gonna wanna talk over the top of each other,
Tom Hollingsworth:and ethernet doesn't like that.
Tom Hollingsworth:So once you had a certain boundary, you kind of have to divide it
Tom Hollingsworth:up into these little domains.
Tom Hollingsworth:Um, collision domains are what we call them, and that's one
Tom Hollingsworth:of the things that a VLAN is.
Tom Hollingsworth:But as we've learned over the years about what we really should be doing,
Tom Hollingsworth:we've kind of built a super set of that.
Tom Hollingsworth:And anyone out there who has been reading any kind of the tech press recently, or
Tom Hollingsworth:been to any trade show in the last couple of years, probably heard of something
Tom Hollingsworth:like Zero Trust Network Architecture or, or, you know, just Zero Trust in general.
Tom Hollingsworth:It's a buzzword.
Tom Hollingsworth:I'm, I'll be the first to admit it, but the principles behind it are fairly sound.
Tom Hollingsworth:what you do is you take the tools that you've already been given, those ones
Tom Hollingsworth:that I told you, make your network team break out in hives, and you try to
Tom Hollingsworth:implement them in such a way as to reduce the complexity of the implementation.
Tom Hollingsworth:And think about like, you know, think about a teenager and they
Tom Hollingsworth:want a, a list of, uh, things that they can do when they get a car.
Tom Hollingsworth:Are you gonna tell them you can do anything you want, but
Tom Hollingsworth:you can't do this and you can't do that and you can't do this?
Tom Hollingsworth:Or are you gonna be more explicit?
Tom Hollingsworth:You can only do these things and if it's not on that list, you can't do it.
Tom Hollingsworth:Well, most people would say, well, I'm only go, I'm gonna do the second
Tom Hollingsworth:thing because I want to make sure that they're only going to school and to
Tom Hollingsworth:work into this one friend's house.
Tom Hollingsworth:But we don't build networks that way.
Tom Hollingsworth:I mean, we, we typically allow as much as possible because of the
Tom Hollingsworth:situations we find ourselves in where something doesn't work right.
Tom Hollingsworth:And we don't know why.
Tom Hollingsworth:So we will put a little catchall at the bottom of the, the access
Tom Hollingsworth:list and go permit everything else.
Tom Hollingsworth:and then we leave it.
Tom Hollingsworth:And that's the worst thing that you can do.
Tom Hollingsworth:And what Zero Trust Network architectures try to do is they try
Tom Hollingsworth:to say, okay, that server over there is running our backup software.
Tom Hollingsworth:What should it, what should communicate with it?
Tom Hollingsworth:And how should it be communicated with, you know, maybe it only needs to accept
Tom Hollingsworth:connections on these three or four ports.
Tom Hollingsworth:Maybe it only accepts connections from these authorized users.
Tom Hollingsworth:And you're effectively creating an isolation for that unit.
Tom Hollingsworth:And if something needs to access it and you're having problems with it, the
Tom Hollingsworth:software usually allows you to kind of dig into that a little bit and go, oh, it
Tom Hollingsworth:looks like that this program did an update and it now needs to communicate over this
Tom Hollingsworth:port, uh, and I need to allow that port.
Tom Hollingsworth:But you're doing it in a, in a way that allows you to kind of control that access.
Tom Hollingsworth:But more importantly, what happens is that when something tries to operate
Tom Hollingsworth:outside of that access control, it slams it shut and hopefully will send
Tom Hollingsworth:you some kind of a warning, you know, Hey, we just noticed that this server
Tom Hollingsworth:over here is trying to communicate with the rest of the network on Port 4 45.
Tom Hollingsworth:and I know it shouldn't be doing that.
Tom Hollingsworth:You need to take a look at it.
Tom Hollingsworth:And so limiting that blast radius, that broadcast capability tends
Tom Hollingsworth:to prevent lateral movement.
Tom Hollingsworth:And like you said, people who are going to attack you are, are
Tom Hollingsworth:going to be dedicated in doing it.
Tom Hollingsworth:Either they're gonna be dedicated to looking for a very specific exploit and
Tom Hollingsworth:just kind of hauling in whatever they can do, or they're gonna be looking to
Tom Hollingsworth:attack you, you specifically, however they can get to you that second kind
Tom Hollingsworth:of attacker, very difficult to block.
Tom Hollingsworth:It's like a door lock, a dedicated burglar is gonna get into your house.
Tom Hollingsworth:You're looking to prevent more of the first one where it's like, oh, we were
Tom Hollingsworth:able to get in through your HVAC system and boy, we're gonna turn this thing loose
Tom Hollingsworth:and see what open file shares you've got out there and what we can do with them.
Tom Hollingsworth:You, you need to create structure in the organization that does not allow
Tom Hollingsworth:people to move laterally that that prevents them from accessing things.
Tom Hollingsworth:Or worse yet, alerts you when things start doing a lot of scanning across
Tom Hollingsworth:your network, looking for those kinds of things because the, the rest of the group
Tom Hollingsworth:that's trying to get into your network doesn't know that stuff's there either.
Tom Hollingsworth:They're gonna have to go looking and just like the burglars that are casing the
Tom Hollingsworth:joint, you need to look for those people.
Prasanna Malaiyandi:So multiple things popped up in my head,
Prasanna Malaiyandi:Tom, as you were talking.
Prasanna Malaiyandi:So the first is, as you're talking about the burglar example, I'm gonna bring this
Prasanna Malaiyandi:up again for the second week, but Curtis had recommended reading The Cuckoo's Egg.
Prasanna Malaiyandi:I don't know if you've read that book.
Prasanna Malaiyandi:Tom.
Prasanna Malaiyandi:Highly recommend you read it.
Prasanna Malaiyandi:It's basically, 1980s, a hacker gets into a mainframe and starts moving
Prasanna Malaiyandi:laterally across all these like military networks and science networks
Prasanna Malaiyandi:because everything was connected.
Prasanna Malaiyandi:And like you said, that example was go and try all the door locks and he
Prasanna Malaiyandi:would try default passwords and some of these systems, like the mainframes,
Prasanna Malaiyandi:people would not change the defaults.
Prasanna Malaiyandi:And so he got in and it was just that lateral movement across
Prasanna Malaiyandi:everything in the environment.
Prasanna Malaiyandi:So that's like the first thing that came to mind as you were talking.
Prasanna Malaiyandi:Um, the other thing that also came to mind is I totally get the reason to have
Prasanna Malaiyandi:like that zero trust and only enables services that, and patterns that are known
Prasanna Malaiyandi:to be valid and disable everything else.
Prasanna Malaiyandi:Uh, my question.
Prasanna Malaiyandi:As a network engineer or operations person, how do
Prasanna Malaiyandi:you manage that at the scale?
Prasanna Malaiyandi:Because there's so many applications, so many servers, it's hard to predict
Prasanna Malaiyandi:what's going to talk with what, um, and coming up with, because
Prasanna Malaiyandi:like, everything's all connected.
Prasanna Malaiyandi:Like in my mind I think about like Facebook and graphs, right?
Prasanna Malaiyandi:Everything is connected in the world, right?
Prasanna Malaiyandi:And so everything in your network to some extent is probably
Prasanna Malaiyandi:connected in some form or fashion.
Prasanna Malaiyandi:So how do you sort of go about even coming up with, okay, these things
Prasanna Malaiyandi:are the things that should be talking to the backup server in your example.
Tom Hollingsworth:So it takes a lot of teamwork because as a network person,
Tom Hollingsworth:I don't care what's running over my network, I just need to make sure that
Tom Hollingsworth:these two things can talk to each other.
Tom Hollingsworth:And so in a way, like if you've ever deployed a server, um, you, you have a
Tom Hollingsworth:list, okay, it needs to communicate, uh, using this protocol over these ports or,
Tom Hollingsworth:you know, uh, think about, uh, opening something like, I need to open HTTPS to
Tom Hollingsworth:the server, but not http because I don't want it to ever communicate over http.
Tom Hollingsworth:And that's actually one of the things that we've noticed a lot recently is that a
Tom Hollingsworth:lot of protocols that used to have their own dedicated ports have now just started
Tom Hollingsworth:writing over, uh, HTTP and https s.
Tom Hollingsworth:Because it's just easier.
Tom Hollingsworth:Uh, bit Torrent was actually one of the first ones to start doing this because
Tom Hollingsworth:they're like, well, eighty's gonna be open anyway, which is the port for http.
Tom Hollingsworth:So we'll just ride on that because most people fire, most people's firewalling
Tom Hollingsworth:systems just allow that by default, because that's what the web uses.
Tom Hollingsworth:And so it gets kind of insidious and you almost have to think at a higher level.
Tom Hollingsworth:So what.
Tom Hollingsworth:it crack open any networking textbook in the world, and they're gonna
Tom Hollingsworth:give you this seven layer model.
Tom Hollingsworth:It's like a seven layer dip from Taco Bell, but there's no refried
Tom Hollingsworth:beans in the seven layer OSI model.
Tom Hollingsworth:But we play a lot in the bottom of that, where the physical connections
Tom Hollingsworth:happen, where the IP addresses allow systems to talk to each other.
Tom Hollingsworth:Once we get above a certain level, that's where the applications take over.
Tom Hollingsworth:And as networking people, we're not as concerned about that.
Tom Hollingsworth:But boy, the server people are because, oh, you know, I need to be able to have
Tom Hollingsworth:these two devices talking to each other.
Tom Hollingsworth:I need to make sure this is all un impeded.
Tom Hollingsworth:And the first thing that happens when two servers can't talk to each other is you
Tom Hollingsworth:gotta find the network people, people.
Tom Hollingsworth:And you're like, you need to tell me what's going on here.
Tom Hollingsworth:And then invariably, like the security team gets drawn in because like, oh no,
Tom Hollingsworth:we told him that he had to block that because nobody should ever be using that.
Tom Hollingsworth:And, and you, you really do have to pull those people together.
Tom Hollingsworth:I mean, think of, you know, think of a book like, uh, gene Kim's Phoenix project.
Tom Hollingsworth:Like you can't work in isolation anymore.
Tom Hollingsworth:As much as we might like to.
Tom Hollingsworth:Because so many things are so inter interdependent now.
Tom Hollingsworth:It's like, you know, the, the old joke is, is what does the server do?
Tom Hollingsworth:I don't know.
Tom Hollingsworth:Unplug the cable and we'll see who screams the loudest.
Tom Hollingsworth:You wanna figure out what people, uh, what port is being used.
Tom Hollingsworth:Let's block it and see who comes to yell at us.
Tom Hollingsworth:Like, that's kind of the way you have to do some of these things.
Tom Hollingsworth:Cuz
Tom Hollingsworth:the other thing, and we, we all know that nobody, nobody ever
Tom Hollingsworth:skips documentation, right?
Tom Hollingsworth:I realized while editing this episode, that we forgot to
Tom Hollingsworth:throw out our disclaimer.
Tom Hollingsworth:Uh, Prasanna and I work for different companies.
Tom Hollingsworth:He works for zoom.
Tom Hollingsworth:I work for Druva.
Tom Hollingsworth:This is not a podcast of either company.
Tom Hollingsworth:It is an independent podcast.
Tom Hollingsworth:So the opinions that you hear are ours.
Tom Hollingsworth:Also, if you'd like to join the podcast, please reach out to me
Tom Hollingsworth:at w Curtis Preston on, uh, at Gmail or at WC Preston on Twitter.
Tom Hollingsworth:Or linkedin.com/i N slash Mr.
Tom Hollingsworth:Backup.
Tom Hollingsworth:And you'll find me, uh, we'd love to have you join and also be sure to
Tom Hollingsworth:rate us at your favorite podcatcher.
Tom Hollingsworth:Thanks a lot.
Tom Hollingsworth:Now onto my silly story.
W. Curtis Preston:You brought up an old memory of mine.
W. Curtis Preston:Literally like my first months in being a cis admin, we were trying to decommission,
W. Curtis Preston:um, uh, the, you know, the, the, the first computer designed to run Unix was the
W. Curtis Preston:three BK and the at and t had a three BK I think it was like a three B 1000.
W. Curtis Preston:And it was their attempt at a multiprocessor architecture.
W. Curtis Preston:And we had this beast and we were trying to decommission it.
W. Curtis Preston:And, uh, we had gotten down to, we had fi you know, and, and we had gotten down
W. Curtis Preston:to that phase where it's like, well, we're just gonna turn it off and whoever
W. Curtis Preston:yells will be the one that we missed.
W. Curtis Preston:Right.
W. Curtis Preston:But I remember the, um, We had, uh, stripped it, all of, all of
W. Curtis Preston:its regular networking cable.
W. Curtis Preston:I don't exactly remember exactly why, but I remember that there was one cable
W. Curtis Preston:left and it was running across the floor and we were doing the last like
W. Curtis Preston:download of, of whatever it was off of this server onto something else.
W. Curtis Preston:And the manager for that cost center was in there and he
W. Curtis Preston:kept stepping on the cable.
W. Curtis Preston:And, um, we told him that he was slowing down the download whenever
W. Curtis Preston:he would step on the cable.
W. Curtis Preston:And, um, we actually caught him, we left him into data center.
W. Curtis Preston:We actually caught him like watching the monitor and like the throughput speed
W. Curtis Preston:and sort of stepping on and stepping up and off and off on the cable.
W. Curtis Preston:Anyway.
W. Curtis Preston:Yeah.
W. Curtis Preston:Good, good stories.
W. Curtis Preston:I, so the question I want to ask you about, all of the things you just talked
W. Curtis Preston:about, is this something built into modern networking equipment or is this, um,
W. Curtis Preston:you know, are these extra applications that I'm buying that then configure
W. Curtis Preston:that networking equipment for me?
Tom Hollingsworth:So it can be both.
Tom Hollingsworth:The, the basics of being able to isolate hosts and configure systems
Tom Hollingsworth:has been built in for years.
Tom Hollingsworth:I mean, anyone can write an a c L, right?
Tom Hollingsworth:The thing is, is that scaling that across a large organization
Tom Hollingsworth:is where it typically falls down.
Tom Hollingsworth:Eventually, your security team can't keep up with all the changes.
Tom Hollingsworth:They throw their hands up in the air and it lies fallow for as long as
Tom Hollingsworth:it takes for you to get infected.
Tom Hollingsworth:So the additional tools that are basically being brought to market and are, are
Tom Hollingsworth:popular now, kind of organize that system.
Tom Hollingsworth:They put a, a, a shiny.
Tom Hollingsworth:UI on it, if you will, to, to go in and say, okay, I, I want to enable port
Tom Hollingsworth:security on these ports because back when I started this port security was,
Tom Hollingsworth:if it isn't being used, shut it off.
Tom Hollingsworth:Just like shut down the port.
Tom Hollingsworth:And then if somebody plugs into it and it doesn't work, well then now we know
Tom Hollingsworth:we need to enable that port and we need to know who's trying to use it.
Tom Hollingsworth:But now you have the ability to like have somebody plug in a device,
Tom Hollingsworth:whether it's an IOT system or what have
Tom Hollingsworth:you, and this, the device will like register with the system.
Tom Hollingsworth:It'll say, Hey, I need access.
Tom Hollingsworth:And then the system can come back and say, Hey, it looks like somebody
Tom Hollingsworth:plugged in an S thermostat over here.
Tom Hollingsworth:Well, that's actually a bad example cause they don't use wires, but you know, a
Tom Hollingsworth:laptop or some other kind of device, you need to go, like check it out.
Tom Hollingsworth:Or you can even set a policy that says, I'm going to allow you for
Tom Hollingsworth:now, but I have the ability to just cut it off if I need to.
Tom Hollingsworth:Or if it's one of these recognized device classes or something like that.
Tom Hollingsworth:So for smaller systems, , you know, for, for smaller organizations, if
Tom Hollingsworth:your IT department isn't already completely overworked, you can't
Tom Hollingsworth:implement some of this by hand.
Tom Hollingsworth:It's just a matter of if it works really well, that means you're gonna
Tom Hollingsworth:be spending a lot of time tuning that system to keep working effectively.
Tom Hollingsworth:And once you get past a certain point, the, uh, the solutions
Tom Hollingsworth:that do this are reassuringly expensive because they're worth it.
W. Curtis Preston:Right.
W. Curtis Preston:Oh, I understood cuz that, that they would help you save the, the, the labor.
W. Curtis Preston:And is there a category of these types of tools that, that a
W. Curtis Preston:category name that we give to them?
Tom Hollingsworth:Uh, there's, there's a bunch of different ones.
Tom Hollingsworth:Uh, access management is typically one that you, you see, um, honestly,
Tom Hollingsworth:tools like Aruba ClearPass or uh, Cisco ice, uh, ise, uh, integrated
Tom Hollingsworth:services engine, or integrated security engine, I forget which one it is.
Tom Hollingsworth:But they're, they're, they're not identity and access management,
Tom Hollingsworth:although they can be integrated that.
Tom Hollingsworth:There are some smaller ones that, that have these capabilities.
Tom Hollingsworth:A lot of it is, is mostly figuring out what you need because there's
Tom Hollingsworth:different, you know, some systems are, are configured so that you're
Tom Hollingsworth:controlling access to devices.
Tom Hollingsworth:I only wanna authorize people to be able to log into this
Tom Hollingsworth:device and make changes to it.
Tom Hollingsworth:Well, that's different than I want to change the way that people
Tom Hollingsworth:in my network are accessing data like that is a different kind of
Tom Hollingsworth:identity and access management.
Tom Hollingsworth:So you need to do a little bit of investigative work to make sure that you
Tom Hollingsworth:are, uh, properly using the right tool.
Tom Hollingsworth:Cause if you spend a lot of money on one that doesn't give you what you want or
Tom Hollingsworth:does a, a, a terrible job of it, then not only are you gonna be upset, but the
Tom Hollingsworth:people that are or authorizing your budget are not gonna be very happy with you.
Prasanna Malaiyandi:Now a lot of these changes, if I think about an
Prasanna Malaiyandi:enterprise environment, things are easier to a fair extent to control, right?
Prasanna Malaiyandi:If you're looking at servers or virtualization, other things like that.
Prasanna Malaiyandi:But then I go to think about other environments like a school, right, where
Prasanna Malaiyandi:you have students coming and going, right?
Prasanna Malaiyandi:Or a stadium or a conference center, right?
Prasanna Malaiyandi:Does it get significantly more difficult to do what you talked
Prasanna Malaiyandi:about, Tom, in those environments?
Prasanna Malaiyandi:Or can the same tools apply there as well?
Tom Hollingsworth:Yes and no.
Tom Hollingsworth:Um, I, I, I'm, I'm the typical IT nerd.
Tom Hollingsworth:The answer is, it depends for whatever question you ask, but I'll tell you
Tom Hollingsworth:that in some ways, um, schools and other places where your user base
Tom Hollingsworth:is not employed directly by you.
Tom Hollingsworth:Can have a slightly easier time if you're willing to, um, sacrifice a little bit.
Tom Hollingsworth:So I know that there are a lot of colleges out there that treat their student
Tom Hollingsworth:dorm networks like the wild, wild west.
Tom Hollingsworth:We don't care what goes on out there, but we're not gonna keep an eye on it either.
Tom Hollingsworth:So like, if
Tom Hollingsworth:there's a, you know, a piece of ransomware or something that's running rampant
Tom Hollingsworth:through the system, all we did is tell you that you had to have your antivirus
Tom Hollingsworth:up to date to be able to join our network.
Tom Hollingsworth:So,
Tom Hollingsworth:so what, uh, the stadiums are actually a, a really interesting, uh, problem
Tom Hollingsworth:too, because not only do you have a a, a group of users that are outside of
Tom Hollingsworth:your control, they're very transient, um, in a lot of those places.
Tom Hollingsworth:Like they, they actually have, uh, wireless networks that are set up
Tom Hollingsworth:so that, um, they can only talk.
Tom Hollingsworth:, like they block all device to device communication, which
Tom Hollingsworth:is something that you can do.
Tom Hollingsworth:It's a little bit more complicated, but it effectively treats, um, the stadium
Tom Hollingsworth:itself like a demilitarized zone in a, uh, in a, in a security structure.
Tom Hollingsworth:So for most people that are, that are familiar with it, you know, you've got the
Tom Hollingsworth:outside internet, which is big and scary.
Tom Hollingsworth:You've got your inside network, which is soft and, and you know,
Tom Hollingsworth:uh, you don't want it to get hurt.
Tom Hollingsworth:And then in the middle you have the dmz, which is basically the moat where
Tom Hollingsworth:you're like, I'm gonna put everything that I don't care if it gets attacked
Tom Hollingsworth:out there so that if it breaks, it can't get back into my network.
Tom Hollingsworth:And so, but the otherwise, the other thing there is I only allow
Tom Hollingsworth:certain traffic to come back through.
Tom Hollingsworth:So if something bad were to happen, I can just basically cut it off and
Tom Hollingsworth:sink it into the moat and I'm done.
W. Curtis Preston:Yeah, I think, uh, hotels have a similar model, right?
W. Curtis Preston:Where the base, uh, I know having, having plugged in multiple devices that
W. Curtis Preston:needed to talk to each other in hotel networks, they don't like that very much.
W. Curtis Preston:Uh, and you end up having to bring basically your own router if, if
W. Curtis Preston:that's something that you want to do.
W. Curtis Preston:Right?
W. Curtis Preston:Um, so the, so it sounded like, um, if I understood you correctly,
W. Curtis Preston:the access management part is this sort of basic security thing, that
W. Curtis Preston:there are tools that do just that, and then there's also this identity
W. Curtis Preston:access, which is a, a bigger pain.
W. Curtis Preston:I would, I would imagine.
W. Curtis Preston:But those that want that, and it sounds like when we put those
W. Curtis Preston:two together, that's what, what we call a SEIM tool, right?
W. Curtis Preston:Is uh, uh, identity and access management.
W. Curtis Preston:But it sounds like there's just an access management.
W. Curtis Preston:That, for those that need just that there, there's smaller and less
W. Curtis Preston:expensive than a full SEIM tool.
W. Curtis Preston:Yeah.
W. Curtis Preston:Not, not inexpensive, but just less expensive.
Tom Hollingsworth:Well, and it, it also matters as to what you're spending
Tom Hollingsworth:your resources on, because there are tools that will do this for free.
Tom Hollingsworth:But they are not supported at all by anybody other than people on a forum.
Tom Hollingsworth:And they'll be glad to tell you that you misconfigured something
Tom Hollingsworth:and go figure it out yourself.
Tom Hollingsworth:Like we, we've dealt with that.
Tom Hollingsworth:And I'm not really crapping on the open source community because
Tom Hollingsworth:they do an amazing job of this.
Tom Hollingsworth:I'm crapping on the fact that open source communities are not as well supported
Tom Hollingsworth:as the bigger players in these markets.
Tom Hollingsworth:And that's honestly where the expensive part comes from.
Tom Hollingsworth:You're not paying for the software, although you, you
Tom Hollingsworth:kind of are in some ways.
Tom Hollingsworth:You're paying for somebody to answer the phone when somebody is like breathing
Tom Hollingsworth:down your neck because something won't work or something won't come online.
Tom Hollingsworth:And so a and a and you're also trying to get to that point where
Tom Hollingsworth:it's, it's not automated as much as it is as low friction as possible.
Tom Hollingsworth:Because what you want in situations is people to just
Tom Hollingsworth:be able to get on the network.
Tom Hollingsworth:That's, that's the thing.
Tom Hollingsworth:If you've ever tried to log into a wifi network that has a captive portal
Tom Hollingsworth:that requires you to like accept a whole bunch of licensing agreements
Tom Hollingsworth:and type your room number in and all the other stuff, you know that it's not
Tom Hollingsworth:the most frustrating thing, but it's definitely not what you want to hear.
Tom Hollingsworth:As opposed to like, oh, this device has already been pre-authorized cuz you logged
Tom Hollingsworth:in with your active directory username.
Tom Hollingsworth:Well, we'll just let it on the network.
Tom Hollingsworth:That's completely frictionless.
Tom Hollingsworth:But the amount of effort that it takes to make it frictionless is where your time
Tom Hollingsworth:and resource invests gonna come from.
Prasanna Malaiyandi:Tom, I know we started this all out with Curtis asking,
Prasanna Malaiyandi:how do you prevent lateral movement in networks right from ransomware?
Prasanna Malaiyandi:Just given the fact that ransomware does move laterally in a lot of networks?
Prasanna Malaiyandi:Does this mean people are not using these tools or have not
Prasanna Malaiyandi:configured the networks correctly?
Prasanna Malaiyandi:Because it seems like if you did all the things that we just talked about, it
Prasanna Malaiyandi:should have prevented a lot of the lateral movement that we see in ransomware today.
Tom Hollingsworth:Well, Prasanna, I'm gonna tell you something
Tom Hollingsworth:that my dad always tell me, and you have to understand.
Tom Hollingsworth:My dad grew up in the country.
Tom Hollingsworth:If a frog had wings, he wouldn't bump his ass every time he hopped.
Tom Hollingsworth:So yes, if you turn on all of these tools, you will cut down on a lot of this stuff.
Tom Hollingsworth:But does that mean your network's not working correctly?
Tom Hollingsworth:No.
Tom Hollingsworth:It just means that we didn't enable all these extra features that we have
Tom Hollingsworth:to keep track of because I can get four, uh, four network ports on a.
Tom Hollingsworth:and plug four devices in there and they're gonna work is the
Tom Hollingsworth:best way for them to work.
Tom Hollingsworth:Absolutely not, but I also don't have to do a whole lot of extra configuration.
Tom Hollingsworth:A lot of people are looking at this from the perspective of, I need to
Tom Hollingsworth:make sure that everything is, is able to communicate with everything else.
Tom Hollingsworth:They're not looking at it like you, like the example you had earlier, Curtis, when
Tom Hollingsworth:you log into the hotel wifi and I can't talk to anything else on the hotel wifi.
Tom Hollingsworth:They're not thinking in a, in an isolation mode.
Tom Hollingsworth:And we're, we're that ship's turning because a lot of people are now
Tom Hollingsworth:realizing that, that that traditional idea of having a very stiff, crunchy
Tom Hollingsworth:perimeter with a very soft internal network doesn't work so well.
Tom Hollingsworth:Because what ends up happening is, is that once people get through
Tom Hollingsworth:the perimeter, they have free reign to do whatever they want.
Tom Hollingsworth:You, you do have to build these controls in place to effectively
Tom Hollingsworth:slow them down or to herd them to places that you want them to go.
Tom Hollingsworth:And that's what a lot of people have spent time developing and working on.
Tom Hollingsworth:And there's varying degrees of success to make that work.
Tom Hollingsworth:It has to shift the mindset though.
Tom Hollingsworth:Um, you know, application people are just turn on all the ports
Tom Hollingsworth:and I'll turn them off later.
Tom Hollingsworth:When I tell you which ones I don't need, you won't, because you'll
Tom Hollingsworth:get busy doing something else.
Tom Hollingsworth:It's like developers, they're like, I'm gonna load everything I can possibly
Tom Hollingsworth:think of in the memory so that I know the library that I need is there.
Tom Hollingsworth:And then you wonder why your, your, uh, application is consuming
Tom Hollingsworth:like three terabytes of ram.
Tom Hollingsworth:It's like, uh, maybe you need to pa pair back a little bit on that.
W. Curtis Preston:Yeah.
W. Curtis Preston:So it, it sounds like these tools are there.
W. Curtis Preston:Uh, I think a lot of people do use them, but you talked about, like in the very
W. Curtis Preston:beginning, you, you said that people's heads are gonna start spinning or
W. Curtis Preston:whatever, because there is a lot of work involved in implementing these things.
W. Curtis Preston:And the moment you flip that switch from, you know, per, you know, from
W. Curtis Preston:everything is permitted to only the things that are permitted or permitted, uh,
W. Curtis Preston:you're gonna get 5,000 tickets, right?
W. Curtis Preston:I can't do this and I can't do that.
W. Curtis Preston:And they, they see that.
W. Curtis Preston:They see that very real worry.
W. Curtis Preston:Uh, and I, and I think it stops many people from implementing this
W. Curtis Preston:because they just see it as the amount of work they're gonna have
W. Curtis Preston:to do to initially implement it.
W. Curtis Preston:Um, they're, and they're not seeing the risk of what's gonna happen when
W. Curtis Preston:they get a ransomware infection, and then it just goes crazy.
Tom Hollingsworth:Most tools that are, are set up like this.
Tom Hollingsworth:Uh, they have a learning mode where they will, you could put 'em in place and
Tom Hollingsworth:they just sit there and they watch for at
Tom Hollingsworth:least the first, you know, week or two.
Tom Hollingsworth:And they're mapping out all of these application dependencies.
Tom Hollingsworth:So, you know, the backup system needs to receive traffic on this port for
Tom Hollingsworth:this application from this subnet.
Tom Hollingsworth:And then it allows you to carefully craft that rule so that only devices
Tom Hollingsworth:from this subnet can talk to that server on these ports and nothing else.
Tom Hollingsworth:And if you let the tool go long enough, you'll be able to like, suss
Tom Hollingsworth:out exactly what you need to know.
Tom Hollingsworth:But yeah, that first day you click the switch to from, you know, allow list to
Tom Hollingsworth:deny a list is just like you're, you're staring at the ticket queue because
Tom Hollingsworth:you're like, oh, what happens if I, if this machine hadn't been turned on for a
Tom Hollingsworth:week or what, you know?
W. Curtis Preston:yeah.
Tom Hollingsworth:Yeah.
Tom Hollingsworth:It just, it, it, it is, it's maddening because you're always gonna wonder if you
Tom Hollingsworth:didn't get the right stuff, but like you said, would you rather be worried about
Tom Hollingsworth:one machine that can't talk to another?
Tom Hollingsworth:Or would you be worrying about the fact that you're getting a phone call from
Tom Hollingsworth:the CIO saying, uh, yeah, the database has just got encrypted by this new flavor
Tom Hollingsworth:of malware that we haven't seen yet.
Tom Hollingsworth:Uh, why did that?
W. Curtis Preston:Yeah.
W. Curtis Preston:Another thing I want to ask you, I wanna sort of move forward into
W. Curtis Preston:the, the ransomware part here.
W. Curtis Preston:Although Prasanna, I'm so glad you basically told us to go backwards.
W. Curtis Preston:You always, you're really good at that, you know, you're really good at
W. Curtis Preston:making me go backwards.
W. Curtis Preston:Uh, anyway, uh, I wanted, so one of the things, so we talked about
W. Curtis Preston:trying to limit lateral movement.
W. Curtis Preston:Another thing that was suggested was to not permit, uh, new, new either
W. Curtis Preston:new domains, like domains that just recently were created, or domains
W. Curtis Preston:that w got recently active, right.
W. Curtis Preston:From a DNS perspective, is that, is that still fall under the networking purview?
W. Curtis Preston:Um, or is that like, is that another world?
Tom Hollingsworth:It, it tend, anything that involves names and not
Tom Hollingsworth:numbers tends to float up towards the application team or the security
Tom Hollingsworth:team.
Tom Hollingsworth:Uh, and the reason for that is because, like you said, like one of the things
Tom Hollingsworth:that, that we see a lot in security now is it's this idea that you wanna black hole
Tom Hollingsworth:things that are, that are relatively new.
Tom Hollingsworth:Like why is this machine suddenly starting to communicate over a d n
Tom Hollingsworth:s name that I've never seen before?
Tom Hollingsworth:But it also
Tom Hollingsworth:requires that your devices have the intelligence to be able to resolve that
Tom Hollingsworth:because, you know, application layer firewalls will see, oh, you are trying to
Tom Hollingsworth:access this service that I don't recognize on a domain that I've never seen before.
Tom Hollingsworth:Whereas a, a lower level, almost like a packet filtering firewall will say,
Tom Hollingsworth:oh, well that's an IP address connection on this port from here to there.
Tom Hollingsworth:Uh, I don't see a reason why I shouldn't be using that.
Tom Hollingsworth:And so, You, You, kind of have to integrate those two things together
Tom Hollingsworth:because like you said, you know, something doesn't look right here
Tom Hollingsworth:because why would it be contacting a brand new DNS name that it should, it
Tom Hollingsworth:has no reason to contact or worse yet?
Tom Hollingsworth:Uh uh.
Tom Hollingsworth:You can ask the people over at SolarWinds.
Tom Hollingsworth:Why is this DLL suddenly talking to .ru addresses?
W. Curtis Preston:right?
W. Curtis Preston:Yeah.
W. Curtis Preston:Well, when he says new domain names, he actually means domain names that were
W. Curtis Preston:like recently registered, not just domain names that are new to your network.
W. Curtis Preston:And then also ones that, that were, they were registered but they had, they hadn't
W. Curtis Preston:been active or something like that.
W. Curtis Preston:So that sounds like that's a d n s uh, you know, there's a d I world, right?
W. Curtis Preston:Um, we had, we had somebody on from that.
W. Curtis Preston:I think we need to have some, because this is, I think that's, , if you can
W. Curtis Preston:reasonably do that, where you could basically push a button, just sort of like
W. Curtis Preston:the, the, the deny the allowed deny thing.
W. Curtis Preston:If you can reasonably say, I, I don't want, I don't want anybody
W. Curtis Preston:talking to domain names that were registered 24 hours ago.
W. Curtis Preston:Right.
W. Curtis Preston:I, I If you could, if you could do something like that, it will of course
W. Curtis Preston:also create some trouble, uh, tickets.
W. Curtis Preston:But I'm thinking far less.
W. Curtis Preston:And if you could do that, it stops to command and control, uh, you
W. Curtis Preston:know, the, the ransomware from reaching out at command and control,
W. Curtis Preston:um,
Tom Hollingsworth:slows the
Tom Hollingsworth:process down.
Tom Hollingsworth:But the one thing I will say there though, is that you need to make sure
Tom Hollingsworth:that your users are expecting that change.
Tom Hollingsworth:Because if it requires you to go out and check a list or, uh, get some kind of
Tom Hollingsworth:una authorization to go to this domain name, even if it adds one second to the
Tom Hollingsworth:resolution time, that's one extra second that people are going to complain about
Tom Hollingsworth:and you know who they're gonna complain.
Tom Hollingsworth:the networking team, because the network isn't working.
Tom Hollingsworth:Not the d n s block list checker or the application that has this built into it.
Tom Hollingsworth:Oh, no, no.
Tom Hollingsworth:It's the network's fault because the packets aren't
Tom Hollingsworth:going where they're supposed to.
W. Curtis Preston:As we used to say back, back when I was, you know,
W. Curtis Preston:when I first said that we, we would say the problem's under the floor.
W. Curtis Preston:Right?
W. Curtis Preston:Uh, meaning, meaning it was a networking problem.
W. Curtis Preston:Um, go ahead, Prasanna.
Prasanna Malaiyandi:So moving on.
Prasanna Malaiyandi:So we talked about how to prevent lateral movement, how to detect these, uh,
Prasanna Malaiyandi:rogue, uh, servers that are coming up.
Prasanna Malaiyandi:One thing I wanted to ask is, so say you do get hit by ransomware, right?
Prasanna Malaiyandi:They're able to move laterally.
Prasanna Malaiyandi:What happens next from a networking perspective?
Prasanna Malaiyandi:Well, I guess two questions.
Prasanna Malaiyandi:One is how do you, how would you go about bringing down your network or sort
Prasanna Malaiyandi:of isolating what needs to be isolated?
Prasanna Malaiyandi:Like how do you actually figure out what's going on in your network?
Prasanna Malaiyandi:And then the second question is, okay, now that you've sort of
Prasanna Malaiyandi:identified that, how do you slowly recover from those situations?
Tom Hollingsworth:Incident response is never fun because
Tom Hollingsworth:it's a whole lot of cleanup.
Tom Hollingsworth:And, uh, and, and the first thing you have to do is you have to,
Tom Hollingsworth:you have to get people out of your network because there's, you know,
Tom Hollingsworth:there's obviously, there's the tools that kind of run on their own.
Tom Hollingsworth:And there are tools that kind of have to be piloted by people.
Tom Hollingsworth:So you have to create, uh, limits on the, on the system to be able to stop that.
Tom Hollingsworth:And fingers crossed that you're not in a situation where your entire
Tom Hollingsworth:network has been taken down by whatever is causing the problem.
Tom Hollingsworth:Because I've seen that before too, where not only does it try to laterally move to
Tom Hollingsworth:infect systems, it also throws up enough extra garbage that you are, it's Inca,
Tom Hollingsworth:you're capable of logging into any of your
Tom Hollingsworth:management networks.
Tom Hollingsworth:So we're lesson number one.
Tom Hollingsworth:Make sure all your management networks are kind of isolated so that you
Tom Hollingsworth:always have the ability to use those.
Tom Hollingsworth:But the first thing that I would.
Tom Hollingsworth:As I would cut off outside access immediately, I would
Tom Hollingsworth:lock the firewall in place.
Tom Hollingsworth:I mean, you don't have to like run through the data center screaming with
Tom Hollingsworth:your hair on fire and start yanking cables out like the alias episode.
Tom Hollingsworth:But you need to be able to lock all of those connections down.
Tom Hollingsworth:And specifically you need to look for ones that, you know, could be like, you know,
Tom Hollingsworth:from really weird external addresses, or worse yet ones that are coming in.
Tom Hollingsworth:Once you've blocked that external access in and out, you gotta do it
Tom Hollingsworth:in both directions because obviously you don't want anything getting out
Tom Hollingsworth:because the two things that I can think of are command and control traffic.
Tom Hollingsworth:If some kind of tool that's being, uh, um, orchestrated or data exfiltration
Tom Hollingsworth:and, and you're like, oh, well I can stop those file transfers.
Tom Hollingsworth:Yeah, look up oil rig.
Tom Hollingsworth:It was, uh, it was able to exfiltrate data through DNS queries.
Tom Hollingsworth:Like that's the kind of crap you have to worry about.
Tom Hollingsworth:So you've gotta lock it down.
Tom Hollingsworth:Then you have to isolate because that's
Tom Hollingsworth:the other thing too.
Prasanna Malaiyandi:But, but before you move on,
W. Curtis Preston:I stop you there?
W. Curtis Preston:Uh, so how, how do you do that, right?
W. Curtis Preston:Is this, is this something where you have to create.
W. Curtis Preston:A button to press up, you know, because this sounds like a lot of little steps
W. Curtis Preston:you probably need to do to do this manually, or is there something I can
W. Curtis Preston:do upfront that says, in the event of a ransomware attack, push this button.
W. Curtis Preston:Hey, gum.
W. Curtis Preston:Shut up.
W. Curtis Preston:Anyway, uh, in the event of a ransomware attack, press this button and it
W. Curtis Preston:does the 10 things I need to do.
W. Curtis Preston:Uh, what, what do you think
Tom Hollingsworth:Some of them do have a big red button press here to, to like
Tom Hollingsworth:terminate all firewall connections.
Tom Hollingsworth:But most of the time you're gonna have to create like a checklist or, or have
Tom Hollingsworth:a system of like, okay, I'm gonna go into these rules and I'm gonna uncheck
Tom Hollingsworth:these five boxes and then I'm gonna hit the terminate connections button to make
Tom Hollingsworth:sure that no new connections can be made.
Tom Hollingsworth:Also, if you have a rule at the bottom of your firewall list that
Tom Hollingsworth:says Permit ip, any, any, take it out
Tom Hollingsworth:now because it's not doing you any good.
Tom Hollingsworth:But, but more importantly, you, you have to, you know, uh, all
Tom Hollingsworth:kill switches have to be wired.
Tom Hollingsworth:, there's no such thing as a magical switch that you can just hit, even if it's one
Tom Hollingsworth:that the, that the provider has given you investigate what it actually does.
Tom Hollingsworth:Does it dump the rules completely?
Tom Hollingsworth:Does it just like suspend the rules until you go in and manually add them?
Tom Hollingsworth:Remember that that could also cut off your connection to the firewall, so
Tom Hollingsworth:you need to have another way to get into it just in case that happens.
Tom Hollingsworth:Another reason for an isolated management network, but the, the idea is, is that
Tom Hollingsworth:you, you, you need to investigate what your options are because God help you
Tom Hollingsworth:if you really do have to run down to the data center and yank the cables
Tom Hollingsworth:out, and if that is a case and, and hey, it's just as valid as anything else.
Tom Hollingsworth:Can you make sure that you have the right keys, that you know which
Tom Hollingsworth:firewall you're yanking out of?
Tom Hollingsworth:Are there any other exits off of your network?
Tom Hollingsworth:Because that's another problem that you may run into.
Tom Hollingsworth:What happens if someone has created another exit off of your network,
Tom Hollingsworth:either accidentally or on purpose?
Tom Hollingsworth:And what happens then?
Tom Hollingsworth:Because you know it's just as easy for me to plug something into your network.
Tom Hollingsworth:And if there's another way off of it, I'm gonna find it.
Prasanna Malaiyandi:Yeah.
Prasanna Malaiyandi:The one other thing though, I know you talked about, and it totally
Prasanna Malaiyandi:makes sense to kill all incoming and outcoming traffic, but just thinking a
Prasanna Malaiyandi:step forward, like when you're dealing with incident response, like doesn't
Prasanna Malaiyandi:that also take out like your chat channels, your slack channels, your
Prasanna Malaiyandi:video conferencing, everything else, like what do you do at that point?
Prasanna Malaiyandi:Is it just hope you have everyone's cell phone numbers?
Tom Hollingsworth:you need to have a plan for out of band incident
Tom Hollingsworth:response because y it's, it, it's just like any crime scene.
Tom Hollingsworth:I need to figure out what's, what's been hit and I need to figure out
Tom Hollingsworth:how much of it is going to spread.
Tom Hollingsworth:And you're thinking to yourself like, I can't shut my network down
Tom Hollingsworth:permanently because you know it's gonna cost me X amount of dollars.
Tom Hollingsworth:Yes, but it's also gonna cost you x plus whatever amount of
Tom Hollingsworth:dollars when the next system gets
Tom Hollingsworth:hit, when it uncovers a device that no, nobody's patched it in years.
Tom Hollingsworth:Um, I'm not gonna lie.
Tom Hollingsworth:Incident response can work over iMessage text threads for a good couple of
Tom Hollingsworth:hours while you try to figure that out.
Tom Hollingsworth:Or, you know, buy your incident response team like those little, you
Tom Hollingsworth:know, hotspots or enable the data plans on their phone so that they can join
Tom Hollingsworth:their laptop there and join a Slack instance outside of your network.
Tom Hollingsworth:because that way nothing is working internal to your network.
Tom Hollingsworth:Because that's the other thing too.
Tom Hollingsworth:If you, if this is something that's particularly insidious on a window
Tom Hollingsworth:system and your incident responders are using Windows systems and they join
Tom Hollingsworth:the network to be able to do incident response and their laptops get compromised
Tom Hollingsworth:because they join the network again, you're gonna feel really, really dumb.
Tom Hollingsworth:It's like, uh, the professional, when they blew up the bomb squad truck, it's like,
Tom Hollingsworth:come on guys, what were you expecting?
W. Curtis Preston:You just reminded me of the, there's a, there's a series
W. Curtis Preston:of commercials and there's one where the commercial is like, it's like a
W. Curtis Preston:horror movie and the, there's a bunch of kid, it's like the, you know, I got
W. Curtis Preston:the guy with the, the, the ax murderers looking for the group of kids, and
W. Curtis Preston:they're like, why don't we go hang out?
W. Curtis Preston:Why don't we go hide in that shed over there with all the, uh, with all
W. Curtis Preston:the, uh, machetes or something like
Tom Hollingsworth:Yeah.
W. Curtis Preston:Um, so, so we talked about blocking external traffic.
W. Curtis Preston:What about blocking internal traffic?
W. Curtis Preston:You know, uh, basically the lateral traffic, uh, be due to the, we
W. Curtis Preston:know we have ransomware and we know it's gonna try to crawl.
W. Curtis Preston:What about blocking that, uh, access?
Tom Hollingsworth:So that's where you hope that your management
Tom Hollingsworth:networks are, um, isolated because the first thing I would do going
Tom Hollingsworth:into a router is shut down the route.
Tom Hollingsworth:Tables prevent, um, traffic from being passed across network boundaries.
Tom Hollingsworth:Um, what you're effectively doing in there is you are
Tom Hollingsworth:containing the damage to one area.
Tom Hollingsworth:Now, yeah, you're gonna take things down, but if you can isolate that network as
Tom Hollingsworth:the location for wherever the problem is, you can then bring other networks
Tom Hollingsworth:back online and be relatively certain that they're not gonna be infected.
Tom Hollingsworth:I really hope that you're not using like, just regular routing, that you
Tom Hollingsworth:have some kind of a security boundary there, because that makes it a whole lot.
Tom Hollingsworth:But you, you've got to think in, in phases.
Tom Hollingsworth:Obviously, you know, using the kill switch is gonna take everything
Tom Hollingsworth:down, but then you have to start, you know, can I bring this back online?
Tom Hollingsworth:Is this going to be infected?
Tom Hollingsworth:What would I be looking for?
Tom Hollingsworth:Um, so I actually have a, a story about this, uh, this happened
Tom Hollingsworth:last year to my children.
Tom Hollingsworth:Uh, one of 'em goes to the public high school here, uh, and I got a rocket
Tom Hollingsworth:text message from their IT department saying, please turn off all public school
Tom Hollingsworth:issue devices until further notice.
Tom Hollingsworth:And I'm like, uhoh, somebody got hit with something fun.
Tom Hollingsworth:And this was like the last day before Christmas break or something.
Tom Hollingsworth:So we went in and we turned off my kid's MacBook, right?
Tom Hollingsworth:So now, immediately I, because I know what the, the thing was, I don't
Tom Hollingsworth:want anybody to like phone home and get infected and then like infect
Tom Hollingsworth:the parents networks or whatever.
Tom Hollingsworth:Okay, no problem.
Tom Hollingsworth:We just shut it off.
Tom Hollingsworth:But then I'm like, I wonder what it could.
Tom Hollingsworth:like I, I'm kind of curious and, and they've, to this day, they've never
Tom Hollingsworth:disclosed what it was, but you would get an email like the next week,
Tom Hollingsworth:oh, if you're using like a, a, a, a corporate phone or if you're using
Tom Hollingsworth:a MacBook, you can turn it back on.
Tom Hollingsworth:Well, that automatically kind of lowers the horizon of, it has to
Tom Hollingsworth:be something that's focused on Windows or something like that.
Tom Hollingsworth:So then you start running through your head of what it could possibly be.
Tom Hollingsworth:Well, an incident response, you have to do the same thing.
Tom Hollingsworth:What server got hit?
Tom Hollingsworth:Oh, well, it was the database server and it was running this version of,
Tom Hollingsworth:uh, you know, windows or SQL server.
Tom Hollingsworth:Okay.
Tom Hollingsworth:Does that mean that Max can get on the network?
Tom Hollingsworth:Do I want them on the network?
Tom Hollingsworth:Is it a situation where even though they can't be infected, they could
Tom Hollingsworth:propagate something to another location?
Tom Hollingsworth:Like there's a lot that you have to go into because obviously the executives are
Tom Hollingsworth:gonna be like, when can we do back up and.
Tom Hollingsworth:and if you're a publicly traded company, oh God, the stockholders are like outdoors
Tom Hollingsworth:with pitchforks and torches and they wanna know when they can get their dividends.
Tom Hollingsworth:And you're like, uh, when I figure out how much of this data got encrypted
Tom Hollingsworth:or stolen, and you're always gonna be fighting that tension and you can't
Tom Hollingsworth:just shut everything off forever.
Tom Hollingsworth:So that's part of incident response is you've got one team working on figuring
Tom Hollingsworth:out how to stop whatever infected you, but you've got another team figuring
Tom Hollingsworth:out how to bring things back online.
Tom Hollingsworth:That's why we call it business continuity now.
Tom Hollingsworth:Right.
Prasanna Malaiyandi:It is interesting about the incident response.
Prasanna Malaiyandi:How have you seen cases?
Prasanna Malaiyandi:Like how do you actually, well, two questions I have.
Prasanna Malaiyandi:How do you figure out like that, this segment, going back to what
Prasanna Malaiyandi:you said, you kill all the routes.
Prasanna Malaiyandi:How do you figure out that this segment is safe or not?
Prasanna Malaiyandi:And then I guess that, yeah, that's actually only one question.
Tom Hollingsworth:Well, so typically what, and, and you're, you're
Tom Hollingsworth:effectively, when you create these boundaries, it's, it's like looking
Tom Hollingsworth:for the hot potato effectively, because unless you, like in the alias episode,
Tom Hollingsworth:just go click all the switches off.
Tom Hollingsworth:Those devices can still communicate to each other at layer two.
Tom Hollingsworth:Now, where you don't wanna have a problem is, is that it's in the data.
Tom Hollingsworth:because if you isolate the layer two data center, now you've got a real problem.
Tom Hollingsworth:Because if those servers, if if it's looking for servers, those
Tom Hollingsworth:servers can still get infected.
Tom Hollingsworth:That's why it's actually better to have like a, you know, a host route or
Tom Hollingsworth:something like that, or something that, that kind of isolates that per unit thing.
Tom Hollingsworth:I mean, honestly, like a V switch is perfect for this because like,
Tom Hollingsworth:if it's not bound for that host, I'm not gonna let it go any further.
Tom Hollingsworth:But effectively what you have to do is you have to look for chatter
Tom Hollingsworth:that's still going on in the network.
Tom Hollingsworth:Like you, you, I've shut all this down.
Tom Hollingsworth:and I told my users to like disable their machines or, or turn them off or
Tom Hollingsworth:whatever, what's still trying to talk.
Tom Hollingsworth:And then you go take that on a case by case basis.
Tom Hollingsworth:Oh, this device is still sending traffic that it's, but
Tom Hollingsworth:it's looking for this server.
Tom Hollingsworth:Okay, well I'm, I, I can shut it off because I know that it's probably safe.
Tom Hollingsworth:But then you run into something like, oh, this thing is chattering
Tom Hollingsworth:an awful lot and it's chattering on a way that it shouldn't be chattering.
Tom Hollingsworth:Like that's how I've gone and found hosts that have been infected, but not
Tom Hollingsworth:by ransomware, but by early malware because they just kept hammering the
Tom Hollingsworth:firewall with these outbound requests.
Tom Hollingsworth:And I'm like, you shouldn't
Tom Hollingsworth:be doing that.
Tom Hollingsworth:So it's, it's almost like a little bit of detective work.
Tom Hollingsworth:The good news is, is that even though the network devices are kind of like
Tom Hollingsworth:dumb from the perspective of I don't care what application is trying to talk,
Tom Hollingsworth:where they're really good at telling you that things are still generating traffic.
Tom Hollingsworth:It's like, oh, this port is still sending a ton of packets f bound
Tom Hollingsworth:for this address on this location.
Tom Hollingsworth:And so then you're like, oh, I think something might be up here.
Prasanna Malaiyandi:Do you ever see cases where people.
Prasanna Malaiyandi:, almost do a, like, create a black hole on the device itself to sort
Prasanna Malaiyandi:of sync the packets there so it doesn't go out, rather than having
Prasanna Malaiyandi:to necessarily do it on the switch.
Tom Hollingsworth:Um, you can, uh, that's actually a really great way to
Tom Hollingsworth:determine what it's trying to contact is to create like a null route on the system.
Tom Hollingsworth:Uh, uh, going all the way back like three or four years.
Tom Hollingsworth:Like Mark Marcus Hutchins, that's how he actually stopped a major outbreak of
Tom Hollingsworth:malware, uh, for all the good it did, and he got arrested by the FBI later.
Tom Hollingsworth:But he basically black hole the dns.
Tom Hollingsworth:He bought the domain black hole it because if that domain name was
Tom Hollingsworth:active, then it would stop propagating.
Tom Hollingsworth:And so he figured that out by saying, oh, I wonder where this is
Tom Hollingsworth:going and I wonder what it's doing.
Tom Hollingsworth:You can do that.
Tom Hollingsworth:And it's actually the next step in incident response, which you've isolated
Tom Hollingsworth:the system, is I wanna see how it behaves and what it's trying to do.
Tom Hollingsworth:Cuz that could give me a clue as to what I got hit with and
Tom Hollingsworth:what they could be looking for.
Tom Hollingsworth:And that gives you, you know, a, a little bit of opportunity, but that's
Tom Hollingsworth:a little bit more of an advanced tool that you would, you would want to use.
Tom Hollingsworth:Uh, just because black holding traffic on a, on a device takes
Tom Hollingsworth:a little bit of setup, especially if you're fighting against people
Tom Hollingsworth:who don't want you to do that.
Prasanna Malaiyandi:Yeah.
W. Curtis Preston:
Speaker:Yeah, so it sounds like.
W. Curtis Preston:
Speaker:A, a lot of the things that you talked about in the last couple of minutes, they
W. Curtis Preston:
Speaker:would be a lot easier to do again, if we segmented the network in the first place,
W. Curtis Preston:
Speaker:right?
W. Curtis Preston:
Speaker:We put people with Windows laptops on one network.
W. Curtis Preston:
Speaker:We put people with Mac laptops on a network, another network.
W. Curtis Preston:
Speaker:We put the, the, the phones right?
W. Curtis Preston:
Speaker:That are doing the wifi.
W. Curtis Preston:
Speaker:We put them on another network.
W. Curtis Preston:
Speaker:Um, and we put servers on a different network.
W. Curtis Preston:
Speaker:We put, maybe we put servers of a different type on, on a different network.
W. Curtis Preston:
Speaker:So that way you could basically say you don't have to tell the,
W. Curtis Preston:
Speaker:the, the users to not do anything.
W. Curtis Preston:
Speaker:You can just say shut off the, the laptop, uh, network.
W. Curtis Preston:
Speaker:Right?
W. Curtis Preston:
Speaker:Um, and you, you shut off the laptop network and so on.
W. Curtis Preston:
Speaker:And, and all the networks that where we don't currently,
W. Curtis Preston:
Speaker:what we're not looking at.
W. Curtis Preston:
Speaker:And then, okay, who's trying to talk?
W. Curtis Preston:
Speaker:Who's trying to talk?
W. Curtis Preston:
Speaker:Why is this server surfing?
W. Curtis Preston:
Speaker:The web
Tom Hollingsworth:Yeah.
W. Curtis Preston:
Speaker:There's nobody over there.
W. Curtis Preston:
Speaker:Why is this server going over report 80?
Tom Hollingsworth:Well, a lot of places already kind of have this by
Tom Hollingsworth:default, even if they didn't realize they were doing it because you have
Tom Hollingsworth:different classes of devices that you wanna treat them differently.
Tom Hollingsworth:Like for example, the uh, um, the server network, we want to have a
Tom Hollingsworth:little bit more security in there.
Tom Hollingsworth:Maybe a little less host to host East to west traffic kind of thing.
Tom Hollingsworth:The wireless network where all the laptops and the devices connect.
Tom Hollingsworth:I'm a little less careful about that because I actually have identity
Tom Hollingsworth:management in place that validates the users when they try to log in.
Tom Hollingsworth:Maybe I have a guest wireless network for my, for people that come into the lobby.
Tom Hollingsworth:That one's wide open to the internet outbound only.
Tom Hollingsworth:So I don't need to worry about that quite as much.
Tom Hollingsworth:And then, you know, like phones and printers and things like that, that
Tom Hollingsworth:have very specific things like, you know, I wouldn't enable Bonura in my
Tom Hollingsworth:internal network, but maybe for the printer vlan I would, because I want
Tom Hollingsworth:people to be able to find a printer.
Tom Hollingsworth:Open up their laptop.
Tom Hollingsworth:So they've already created these segments.
Tom Hollingsworth:You just have to know where the buttons are to shut them off.
Tom Hollingsworth:So maybe the example is I wanna isolate the servers from the rest
Tom Hollingsworth:of the network, cuz I think there's something in there, but I can still
Tom Hollingsworth:leave the wireless network up.
Tom Hollingsworth:Maybe have everybody join the guest access network and force them all
Tom Hollingsworth:out to the internet to do, you know, incident response or chat channels
Tom Hollingsworth:or something like that where I'm, you know, but I'm creating these bounds so
Tom Hollingsworth:that traffic flows one direction only, or it prevents certain things inside
Tom Hollingsworth:of other areas because, you know, there's nothing to say like the, you
Tom Hollingsworth:know, the, the, uh, s IDs that are on printers that are like, you know, set up,
Tom Hollingsworth:uh, set me up or something like that can't be compromised.
Tom Hollingsworth:And then if they can get into your printer network, it's like,
Tom Hollingsworth:oh crap, where can they go from?
W. Curtis Preston:Yeah.
W. Curtis Preston:And, and Bonjour of course would be the, um, I, I don't know how would
W. Curtis Preston:I define
Prasanna Malaiyandi:file sharing.
Tom Hollingsworth:It, it is, it's almost like an auto configuration announcement,
Tom Hollingsworth:uh, setting where, uh, it, it, and you can thank Steve Jobs for this.
Tom Hollingsworth:He's like, I hate setting up printers.
Tom Hollingsworth:And so basically what he did is he set up a system so that the printers
Tom Hollingsworth:can announce that they exist.
Tom Hollingsworth:And your laptop is constantly listening for these.
Tom Hollingsworth:Bonura is another one of those protocols that is extra chatty and you kinda
Tom Hollingsworth:wanna put bounds on it so that like you don't have the Apple TV four hallways
Tom Hollingsworth:down announcing itself to the people in accounting because one, it's annoying.
Tom Hollingsworth:And two, you never know when you're gonna do something you're not supposed to.
Prasanna Malaiyandi:Interesting.
Prasanna Malaiyandi:So yeah, I guess a lot of these are really around setting up
Prasanna Malaiyandi:that initial network properly.
Prasanna Malaiyandi:So then when you do have these issues, you can recover quickly and
Prasanna Malaiyandi:identify and then recover quickly.
Prasanna Malaiyandi:Right?
Prasanna Malaiyandi:But if you don't have that initial setup done, then you're
Prasanna Malaiyandi:in for a world of hurt, I guess.
Tom Hollingsworth:and not just initial setup.
Tom Hollingsworth:You actually do have to treat the network like a living, breathing organism.
Tom Hollingsworth:I can't think of a single server admin out there that installs,
Tom Hollingsworth:you know, windows server.
Tom Hollingsworth:What are we up now?
Tom Hollingsworth:20 20, 20 23 Windows, server X, I don't know, installs it
Tom Hollingsworth:and then never patches it.
Tom Hollingsworth:Never
Tom Hollingsworth:touches it again.
Tom Hollingsworth:Like, like you people are probably just shaking, even thinking.
Tom Hollingsworth:, you cannot configure a network and then just leave it alone.
Tom Hollingsworth:You do have to go in and, and tweak things and move things and change things.
Tom Hollingsworth:And, you know, not just when you're trying to fix a broken thing,
Tom Hollingsworth:either, you have to like, okay, is this subnet big enough for the
Tom Hollingsworth:number of hosts that are in it?
Tom Hollingsworth:Should I create routes over here?
Tom Hollingsworth:It looks like there's a lot of extra traffic going on over this direction.
Tom Hollingsworth:Maybe I need to disallow that because it looks like it's something
Tom Hollingsworth:that shouldn't be happening.
Tom Hollingsworth:Like, if you're not constantly pruning back what you are working on then,
Tom Hollingsworth:and that's the problem that a lot of the, the, uh, ransomware writers have
Tom Hollingsworth:figured out, like a lot of, a lot of their secrets, if you wanna call them,
Tom Hollingsworth:that are just inadequate it support.
Tom Hollingsworth:Like, we're gonna hope that you had left this on by default and we're
Tom Hollingsworth:gonna take advantage of it and use it.
Tom Hollingsworth:And if you did, I'm sorry, but like, you know, if any best practices
Tom Hollingsworth:guide out there says, shut that off, and you didn't shut it off,
Tom Hollingsworth:are you in that big of a hurry?
W. Curtis Preston:Yeah, well we're, we're living in a world
W. Curtis Preston:where, uh, you know, people don't even change their default password.
W. Curtis Preston:So, um, listen, here's the thing, Tom, my plumber's here, so, uh, I, I, you
W. Curtis Preston:know, I got a tradesman that actually showed up at two o'clock when he said
W. Curtis Preston:he was gonna be here at two o'clock.
W. Curtis Preston:So I gotta , we gotta shut this baby down.
W. Curtis Preston:Uh, Tom, this has been, this has been a great conversation.
W. Curtis Preston:Um, so thanks, thanks a lot.
Tom Hollingsworth:Well, thanks for having me.
Tom Hollingsworth:It's, it's been fun to talk about networking with, uh, with some folks
Tom Hollingsworth:that coming at it from a slightly different perspective and understanding,
Tom Hollingsworth:you know, what are we trying to accomplish with it, and in some
Tom Hollingsworth:cases, what are we trying to disallow?
Prasanna Malaiyandi:Hmm,
W. Curtis Preston:Absolutely.
W. Curtis Preston:Thanks again, Prasanna, once again, making me go backwards,
Prasanna Malaiyandi:I, you know me, I try, you take one step back, two steps
Prasanna Malaiyandi:forward or something like that, right?
W. Curtis Preston:something like that.
W. Curtis Preston:I
W. Curtis Preston:like that.
W. Curtis Preston:All right.
W. Curtis Preston:And thanks again to our listeners.
W. Curtis Preston:Remember to subscribe so that you can restore it all.