WEBVTT 01:35.180 --> 01:38.820 Make sure it's not just me who's seeing it weird. 01:44.560 --> 01:47.100 So now they should see the three of us. 01:52.330 --> 01:54.290 Oh yeah, I see us. 01:54.650 --> 01:55.770 You see us? 01:55.910 --> 01:57.670 Yeah, I just went to the Twitch stream. 01:57.670 --> 01:58.310 Oh, excellent. 01:58.310 --> 01:59.510 Which Twitch stream? 02:02.190 --> 02:04.730 I hear myself now, too. 02:05.410 --> 02:06.650 Okay, that's fantastic. 02:06.730 --> 02:10.050 We are a professional organization here on a Friday night. 02:11.190 --> 02:13.690 Yeah, we're going to call that one my fault. 02:13.690 --> 02:14.950 Okay, cool. 02:16.310 --> 02:19.450 Welcome to Q&A with Patrick Wardle. 02:19.450 --> 02:26.330 We are going to be talking about some macOS stuff and some stuff kind of adjacent to Microsoft Office. 02:27.470 --> 02:31.970 I am Jurist, and the other goon that you see here is Fallible. 02:32.110 --> 02:35.770 And we're going to be helping ask Patrick some questions this evening. 02:35.770 --> 02:38.470 And it's good to see you all in the chat. 02:38.470 --> 02:43.290 Patrick, why don't you take a minute to introduce yourself to everybody? 02:43.290 --> 02:47.890 Because I know that in your talk, you kind of dove right in into your content. 02:47.890 --> 02:51.590 So take a minute, say hello to everybody, tell us a little bit about yourself. 02:52.210 --> 02:52.890 Sure. 02:52.890 --> 02:55.130 Aloha, my name is Patrick Wardle. 02:55.130 --> 02:58.630 I am a principal security researcher at Jamf. 02:58.630 --> 03:05.110 I'm also the creator of the Mac security website and tool suite, Objective-C. 03:05.110 --> 03:09.430 I have been fortunate enough to talk at a few DEF CONs in the past. 03:09.430 --> 03:13.610 It's always one of my favorite events to talk nerdy at. 03:13.970 --> 03:18.750 This year, virtual, you know, a little bummed we didn't all get to hang out together in Vegas. 03:18.750 --> 03:21.830 But I think it's important that we're all staying safe and healthy. 03:21.890 --> 03:26.010 And actually connecting online is kind of super hacker-ish. 03:26.010 --> 03:31.250 So I'm stoked you're all here to chat a little bit more about my talk, open Q&A. 03:31.390 --> 03:32.750 Again, welcome. 03:33.590 --> 03:35.530 Well, thank you for being here. 03:35.530 --> 03:36.890 We really appreciate it. 03:36.890 --> 03:41.610 It's nice to get some folks who want to come present this way. 03:41.750 --> 03:47.110 So Sneakernet gave us what they're considering to be a softball question. 03:47.110 --> 03:51.270 Is SYLK the old file format you've come across? 03:51.270 --> 03:57.810 Is there a way to programmatically scan macOS apps for what kind of files they handle? 03:57.810 --> 03:58.770 Entitlements? 03:58.770 --> 04:00.810 Particular API usage? 04:01.890 --> 04:03.870 Yeah, so that's a great question. 04:03.870 --> 04:09.650 The first place I would look at is in something called the Launch Services Database. 04:09.650 --> 04:14.130 And you can enumerate this with the ls register command. 04:14.130 --> 04:23.130 And what it will basically do is it will dump all the file type and application associations on your macOS system. 04:23.130 --> 04:27.690 So for example, you can see what applications have registered for HTML files. 04:27.690 --> 04:31.170 What applications have registered to handle documents. 04:31.190 --> 04:36.730 In this case, what type of applications perhaps support these SYLK files. 04:36.730 --> 04:38.330 So that's kind of where I would start. 04:38.330 --> 04:41.050 It gives you a global overview of that. 04:41.250 --> 04:44.910 So if you just Google ls register, again, it's a macOS command. 04:44.910 --> 04:48.310 You run it with the dash dump flag and it will dump this database. 04:48.490 --> 04:54.430 You can also look at an application's info.plist file, which is something that all applications have. 04:54.430 --> 05:06.750 And in there, they can have a set, it's actually an array, a dictionary of key value pairs that kind of tell the operating system what type of applications, sorry, what kind of files they support. 05:06.750 --> 05:10.170 And this is actually how that database gets populated. 05:10.290 --> 05:15.970 So for example, Microsoft Office lists the doc files and file formats it supports. 05:15.970 --> 05:21.250 Obviously a browser will have a large list including HTML files, probably PDFs, etc. 05:21.250 --> 05:26.010 That's a great place to start because then you can see the file formats. 05:26.010 --> 05:31.110 And then I would look at the more esoteric or unrecognized ones and start fuzzing or playing with that. 05:31.110 --> 05:46.690 Because it's kind of mentioned in my talk, the reason that this vulnerability existed, specifically the automatic execution of macros, was that Microsoft actually has two separate code paths for handling macros based on these file types. 05:46.690 --> 05:55.530 Obviously the main one for documents, and then a whole separate archaic code path that probably no one ever looked at for these older file formats. 05:55.530 --> 06:01.950 Always a good idea to look for these more esoteric, ancient file formats because there's a lot of security bugs there. 06:01.950 --> 06:06.490 Because they were created in a time when security wasn't really a priority. 06:07.450 --> 06:14.710 Any time an afterthought gets pulled forward into what's happening now is probably an interesting space. 06:14.710 --> 06:15.750 Exactly. 06:17.930 --> 06:18.650 Cool. 06:18.650 --> 06:21.870 Next question coming in also from Sneakernet. 06:21.930 --> 06:24.770 Is there a way to programmatically scan Mac apps? 06:24.770 --> 06:26.350 Oh, we did that one already. 06:27.230 --> 06:28.270 Let's see here. 06:28.270 --> 06:39.070 Have you considered trying to do something similar to this kind of research with iPad OS or any other kind of non-Windows OS or mobile OS? 06:40.070 --> 06:41.430 That's a great question. 06:41.430 --> 06:44.450 I predominantly focus on Mac for two reasons. 06:44.450 --> 06:50.330 First, my personal opinion is it's really good to get really niche in whatever area that interests. 06:50.330 --> 06:56.550 That's just something that I've found to kind of have a lot of success in my InfoSec security career. 06:56.850 --> 07:05.950 The other fact, and yes, I will admit this, is hacking Mac is far simpler than hacking an iOS operating system or iPad OS. 07:06.070 --> 07:10.010 Largely, this is just because of how locked down that operating system is. 07:10.010 --> 07:22.510 So I think there has been some research done in the past based on custom URL handling, which is largely how applications and certain file formats are kind of connected in a way on iOS. 07:22.790 --> 07:35.490 But even if you found some interesting issues there, you would have to break out of the sandbox and then deal with a lot of the extra constraints that iOS and iPad OS kind of stack on top. 07:35.490 --> 07:39.030 That with Mac OS, you really don't have to worry about compulsion. 07:39.030 --> 07:44.250 We did have to find a new sandbox escape, but we showed that was pretty trivial to do. 07:44.250 --> 07:46.030 And there's been kind of history of that. 07:46.170 --> 07:51.130 So, you know, the TLDR, iOS is just really a hard target. 07:51.510 --> 07:54.470 So I'll probably just stick with Macs for now. 07:54.730 --> 08:04.310 So that's an interesting statement, though, that you found that getting really niche is the thing that helps you continue to find new interesting vulnerabilities. 08:04.310 --> 08:07.730 So you're keeping your target list really small. 08:07.730 --> 08:10.130 Can you talk about that any more? 08:10.130 --> 08:15.250 And what are some of the strengths that that's bringing you? 08:15.250 --> 08:21.130 And can you think of anything that you're missing that maybe if there was one more thing you wanted to add? 08:22.190 --> 08:22.770 Yeah, I know. 08:22.770 --> 08:27.770 And that's something that, you know, as I grow older and wiser, it's something that resonates really well with me. 08:27.770 --> 08:34.750 So , you know, a long time ago, I used to work at the NSA, National Security Agency, everyone's favorite U.S. 08:34.750 --> 08:36.310 government spy agency. 08:36.310 --> 08:38.850 And I remember when I got there, I was an intern. 08:39.130 --> 08:45.970 And the intern program, you kind of bounce around from different offices, kind of sampling different activities, let's say. 08:46.010 --> 08:55.950 And I remember thinking, I want to be good at all of this, like crypto and like mercenary malware, writing Windows exploits and hacking satellites, like all the really cool stuff the NSA does. 08:56.430 --> 09:02.290 And I got to a point where I was like, you know, it's just impossible to have depth in so much breadth. 09:02.570 --> 09:05.750 So I said, look, I'm going to kind of focus on one specific thing. 09:06.350 --> 09:11.430 And actually, it was only when I left the NSA was when I really started focusing on Macs. 09:11.650 --> 09:17.910 The reason for that was, at the NSA, I did predominantly Windows stuff. 09:18.290 --> 09:25.130 And so when I left, I wanted to still use my foundational skills of reverse engineering, vulnerability discovery, exploit development. 09:25.130 --> 09:27.270 But I didn't want to do it on the same platform. 09:27.270 --> 09:31.550 I was kind of poking around with the NSA, just it's good not to cross any lines. 09:31.550 --> 09:33.470 And, you know, you don't want to piss off the NSA. 09:33.470 --> 09:35.470 I said, hey, look, let me focus on Mac. 09:35.690 --> 09:40.670 I can use my same skill sets, but it's a separate platform, so I probably won't step on any of those. 09:42.030 --> 09:45.630 And moving forward with that, I really kind of doubled down on that. 09:45.630 --> 09:49.490 And it really allowed me to get a lot of depth in the topic. 09:49.490 --> 10:01.310 And I've noticed for, you know, finding new vulnerabilities, giving conference talks, right, at least for me, having that depth has really allowed me to become somewhat of an expert in the space, I would say. 10:01.310 --> 10:09.990 And allowed me to really dig more into maybe the more esoteric parts of the operating system where a lot of vulnerabilities lie. 10:09.990 --> 10:18.110 Whereas if I was trying to do that across maybe multiple operating systems and multiple platforms, it's just, I think, impossible to gain that much depth. 10:18.110 --> 10:20.630 So that's something that's just really worked for me. 10:20.630 --> 10:30.030 I would say the one downside is sometimes you might miss attacks that work on one platform that might have a conceptually similar vulnerability on that class. 10:30.030 --> 10:34.150 One great example I can think of is DLL or dynamic hijacking. 10:34.150 --> 10:37.610 This is a very common kind of attack scenario on Windows. 10:37.890 --> 10:49.190 And I, you know, when I was still kind of coming into the Mac space, I decided to see if macOS was vulnerable, at least conceptually, to the idea of hijacking dynamic libraries based on search path. 10:49.190 --> 10:54.710 And it turned out it was, and I just happened to be the first person that kind of dug into that and talked about it. 10:54.710 --> 11:00.630 So I still think it's good to keep your eyes and ears open and see what other research other people are doing. 11:01.290 --> 11:05.870 Just to be inspired and then kind of say, hey, is this something I can bring into my platform? 11:06.350 --> 11:13.990 But again, I've had a lot of success really focusing just on one platform, you know, macOS, not even iOS as much. 11:14.030 --> 11:18.350 So again, to me, that's worked really well, and I think it's a good nugget of advice. 11:18.350 --> 11:31.930 Yeah, thank you for talking about that a bit, because it's nice to hear somebody who's gotten a lot of success with a pattern like that, because there's many different patterns that I've been hearing about even this weekend. 11:31.930 --> 11:35.030 So it's nice to get that reinforcement. 11:35.230 --> 11:38.510 Yeah, I would agree with that, because I do a lot of digital forensics, right? 11:38.590 --> 11:50.310 And, you know, so I see a lot of Windows stuff come across, and I see a lot of iOS stuff, and it's kind of difficult to know, hey, you know, if I'm going to dedicate some time to build up some skills, you know, should it be broad-based, should it be targeted? 11:50.310 --> 11:54.050 And again, I'm digging what you're throwing down there. 11:55.530 --> 11:56.410 Next question. 11:56.410 --> 12:06.270 Okay, so you showed how putting a zip file into the login items, that in turn contains a plist with a launch agent, right? 12:06.270 --> 12:11.470 So does macOS really register launch agents on the creation of the file? 12:11.470 --> 12:14.910 In this case, creating it via an on-zip. 12:17.110 --> 12:17.790 Almost. 12:17.790 --> 12:22.110 So actually what it does is it automatically processes it on the next login. 12:22.110 --> 12:33.630 So it doesn't trigger it right away on creation, but on the next login, macOS will automatically just enumerate all the property lists that are created in the launch agent directory. 12:33.630 --> 12:35.290 It does the same thing with launch statements. 12:35.290 --> 12:38.570 And any property list it finds, it just runs it. 12:38.570 --> 12:47.550 So that's really kind of a neat thing that we were able to leverage as a mechanism to get this kind of code execution outside the sandbox. 12:47.550 --> 12:53.470 The only downside is you then have to kind of wait until the user re-logs in. 12:53.470 --> 12:59.970 But, you know, I like to say, you know, humans are impatient, but our exploits, our malware, you know, don't have to be, right? 12:59.970 --> 13:10.050 If we drop this launch agent and we have to wait two or three days, or even a week, until the user re-logs in, and then we get a callback, like, so be it, right? 13:10.050 --> 13:12.770 Generally we're not in that much of a rush. 13:12.770 --> 13:20.610 But it is interesting that macOS kind of automatically runs those, and something that we can, in this scenario, leverage to our own benefit. 13:22.210 --> 13:23.050 Sure. 13:23.050 --> 13:25.110 Follow-up from the same person that asked the question. 13:25.110 --> 13:28.450 Any plist it can find on the file system? 13:29.870 --> 13:41.450 No, it actually has to be in the launch agent directory, which is either in tilde user slash library launch agent or slash library slash launch agents. 13:41.450 --> 13:44.690 So macOS will look in those specific directories. 13:44.690 --> 13:48.150 It looks for other items in other directories. 13:48.150 --> 13:53.890 For example, there are other launch daemon directories, which it looks for other property lists. 13:53.890 --> 13:57.830 But again, those have to be in those specific directories. 13:58.450 --> 13:59.330 Cool. 13:59.590 --> 14:04.350 So, you know, a lot of this starts by you talking about macro attacks. 14:04.350 --> 14:08.010 And macro attacks have been popular on Windows for a long time. 14:08.010 --> 14:17.350 In fact, using macros inside of Office documents, I mean, you and I are roughly the same age, that's how you would get out of, like, the net nanny kind of stuff? 14:17.350 --> 14:25.390 Or you get around the stuff that they put on stuff at high school or middle school so you couldn't get on the internet, right? 14:25.390 --> 14:25.750 You know? 14:25.750 --> 14:26.370 Yeah. 14:26.370 --> 14:27.610 Sensual limitations is good? 14:27.610 --> 14:29.150 Well, it's fine now. 14:30.290 --> 14:35.470 So it is bananas to me that this stuff kind of persists now. 14:35.830 --> 14:42.330 Do you think that this is kind of a trend towards macro-based attacks towards macOS? 14:42.330 --> 14:51.270 Or is this just kind of a situation where, you know, the guys are, you know, if you've got a hammer in your hand, everything looks like a nail kind of a situation? 14:52.410 --> 14:57.710 Yeah, no, it's interesting because I think, well, we see two things happening. 14:57.710 --> 14:59.490 Maps are definitely becoming more prevalent. 14:59.810 --> 15:05.130 You know, we've seen this, especially in the consumer space, but now also in the enterprise space. 15:05.130 --> 15:08.110 And I think that's one of the reasons this is very anecdotal. 15:08.110 --> 15:10.270 I don't have necessarily data to back this up. 15:10.270 --> 15:15.730 But, you know, you go to a college campus even three or four or five years ago, everyone has Macs, right? 15:15.890 --> 15:20.290 And now those students have graduated or entered the workforce. 15:20.370 --> 15:20.970 What do they want? 15:20.970 --> 15:22.110 They want Mac computers. 15:22.370 --> 15:23.490 Understandably so, right? 15:23.570 --> 15:28.110 So we're kind of starting to see growth in the enterprise of Macs as well. 15:28.110 --> 15:32.510 Apple obviously also pushes for Macs in the enterprise. 15:32.510 --> 15:35.210 They have great hardware, great software. 15:35.750 --> 15:38.830 So hackers are obviously very opportunistic. 15:38.830 --> 15:43.190 So as they see an increase in targets, they're obviously going to start attacking them. 15:43.190 --> 15:47.390 So one of the things we see is we see hackers developing Mac-specific attacks. 15:47.390 --> 15:51.750 And we've seen this trend, I would say, in the last year or two, almost taking off. 15:51.750 --> 16:07.330 At the same time, in parallel, the other thing we see, and macros is a great example, is we see Windows-based attackers or Windows-based malware that have had success on the Windows platform kind of hoarding those techniques over. 16:07.330 --> 16:14.790 So obviously, as you mentioned, macros on Windows has a very illustrious history, a lot of success. 16:14.790 --> 16:18.890 So those same attacks can work on macros. 16:18.890 --> 16:22.050 So hackers are kind of like, hey, we know how these macros work. 16:22.050 --> 16:23.190 We have the infrastructure. 16:23.190 --> 16:24.610 We have experience. 16:24.670 --> 16:27.290 Why not target Mac users using this? 16:27.290 --> 16:36.910 So macros is probably the best example of traditionally Windows infection vector, let's say, being hoarded over or brought over to macros. 16:36.910 --> 16:41.030 I think in a direct response to Macs increasing in the enterprise. 16:41.030 --> 16:44.630 Because these macro-based attacks still require Microsoft products. 16:44.630 --> 16:51.310 And the average consumer is probably going to be using Apple's Office apps, which aren't susceptible to macro-based attacks. 16:51.310 --> 17:01.390 Whereas in the enterprise, I think that's where we see the uptick in the installation of these Microsoft products on Macs, thereby opening the door for these macro-based attacks. 17:01.390 --> 17:13.490 However, though, we also see, for example, adware that's been predominantly targeting Windows via Chrome on Windows or Edge or Internet Explorer. 17:13.530 --> 17:15.190 Same kind of idea, right? 17:15.190 --> 17:21.430 Hackers and malware writers have success on that and say, hey, we can port these to Mac pretty easily. 17:21.430 --> 17:27.010 It's kind of cross-platform, these techniques and these malicious extensions we create. 17:27.010 --> 17:32.370 So, you know, why don't we start targeting Mac users because they're growing in numbers. 17:32.370 --> 17:42.990 So we're definitely seeing more and more of these Windows, these kind of like old school or very well-known Windows-based infection vectors and attacks now kind of showing up targeting Macs specifically. 17:42.990 --> 17:55.490 And it's interesting because I think Mac users maybe are at more risk because, you know, it's like what Mac user thinks that they can get a macro virus on their Mac, like zero, right? 17:55.490 --> 18:01.450 Traditionally, Apple's marketing has kind of put out the message that Macs are immune. 18:01.790 --> 18:04.250 And so a lot of Mac users believe that. 18:04.250 --> 18:10.530 So whereas someone on a Windows computer might not open a Word document from a random email, a Mac user might. 18:10.530 --> 18:20.210 So hackers may be having a better success rate actually by targeting Mac users, you know, using these kind of well-known techniques that might not fly on Windows anymore. 18:20.210 --> 18:28.470 Or for that matter, not know that the office on the Mac can support some of that stuff that would be also running over on the Windows side, right? 18:28.730 --> 18:33.270 You know, I wouldn't expect a VPK macro to just go ahead and run okay. 18:33.270 --> 18:34.410 It's crazy town. 18:35.310 --> 18:36.450 We love it. 18:38.110 --> 18:44.930 There was a little bit of a follow up from JKBCKR who asked the plist question. 18:44.930 --> 18:46.870 I'll just pop this out here. 18:46.870 --> 18:47.710 Oh, I got it. 18:47.710 --> 18:58.330 The zip was placed into the library and extracted a folder called launch agents with the plist inside, which is the correct location for launch agents. 18:58.870 --> 19:02.070 Okay, so a quick follow up if that's okay. 19:02.130 --> 19:05.990 Does this only work if there was a no launch agents initially? 19:05.990 --> 19:11.170 Otherwise, archive utility would rename that launch agents to, right? 19:11.310 --> 19:13.550 Yes, and that's actually a really good point. 19:13.550 --> 19:22.750 So the reason this generally works is because on a default install of macOS, there's no launch agent directory under the user's directory. 19:23.230 --> 19:26.450 So there is one in the slash library directory. 19:26.450 --> 19:29.250 We couldn't write to that location from the sandbox. 19:29.250 --> 19:32.590 So what we could do, though, is we could write to the user's library directory, right? 19:32.590 --> 19:40.850 To the slash library, put a specially crafted zip file there, and then the archive utility would create the launch agent directory for us. 19:40.850 --> 19:49.550 Because, again, we could also not create or write a plist to that directory because Microsoft's patch specifically forbade that. 19:49.550 --> 19:55.250 So, yes, if that launch agent directory is already there, this specific attack venue would fail. 19:55.250 --> 20:07.530 What we could possibly do, though, is create files in other locations and perhaps create a .bashrc file or some other file that leads to code execution. 20:07.530 --> 20:15.030 Someone also mentioned perhaps you could do something with symlinks, so maybe make a zip file with symlinks. 20:15.030 --> 20:16.850 I haven't really dug into that. 20:16.950 --> 20:26.670 But I think the fact that we can, outside the sandbox, create kind of arbitrary files, the launch agent path was really just the first one I tried that worked. 20:26.670 --> 20:35.870 But there might be other venues that are more globally applicable that, for example, wouldn't fail if the launch agent directory was already there. 20:35.870 --> 20:39.910 So that's a really good question and an excellent point to make. 20:42.150 --> 20:42.830 Excellent. 20:42.830 --> 20:43.510 Okay. 20:43.810 --> 20:47.690 We'll step back for a second to Sneakernet has another question. 20:47.690 --> 20:51.230 Are there any Apple-specific protocols you found really interesting? 20:51.230 --> 20:55.590 Protocols can be either in a process in the same system or between devices. 20:55.590 --> 20:59.330 This is, for example, Sidecar between laptop and iPad. 21:00.210 --> 21:10.410 Yeah, so the IPC mechanisms in macOS are full of security vulnerabilities or have been in the past. 21:10.490 --> 21:15.290 So one great example is just the handling of these custom URL schemes. 21:15.290 --> 21:27.750 So it turns out that if an application supports a file format or supports a custom URL scheme, a custom URL scheme can be like blah, colon, slash, slash, anything. 21:28.310 --> 21:29.790 You know, HTTP would be one example. 21:29.790 --> 21:36.270 But applications can also create their own custom URL handlers as a kind of lightweight IPC mechanism. 21:36.270 --> 21:37.910 And this is used legitimately. 21:38.550 --> 21:49.470 If an application contains a custom URL handler, as soon as it hits the file system, macOS actually parses that application and registers it as a custom URL handler. 21:49.470 --> 21:53.350 A URL can then be launched from the browser. 21:53.450 --> 22:02.690 Luckily, recent versions of browsers now will alert the user, basically saying, hey, a web page is trying to make a custom URL request. 22:02.690 --> 22:04.890 But in the past, that was not the case. 22:04.890 --> 22:11.710 And we actually saw the Wingtail APT group abuse this technique to target Mac users specifically. 22:11.730 --> 22:14.350 So their exploit, you browse through a website. 22:14.350 --> 22:18.890 In the background, it would download an application that handled a custom URL scheme. 22:18.890 --> 22:25.830 macOS would automatically register that behind the scenes as soon as that application hit the file system. 22:26.230 --> 22:32.150 Their exploit code would then just make a URL request from the malicious website, which is totally legitimate. 22:32.150 --> 22:33.230 It's something you can do. 22:33.930 --> 22:36.950 macOS would look and say, hey, yeah, I have an application that can handle that. 22:36.950 --> 22:42.730 And then blindly and naively launch the malware, which had just been downloaded because it had this custom URL. 22:42.730 --> 22:53.510 So these custom URL schemes are kind of a Mac-specific protocol or an IPC mechanism where there are some interesting issues, especially in the past. 22:53.670 --> 22:58.910 I think my other favorite protocol or IPC mechanism is XPC. 22:59.170 --> 23:02.970 Ian Beer at Google has done some great work finding all sorts of vulnerabilities. 23:03.270 --> 23:08.810 Some other Google Project Zero, such as Brandon, researchers have found bugs as well. 23:08.810 --> 23:14.050 And basically, XPC is just a way where a client can talk to usually a privileged server. 23:14.710 --> 23:21.010 And so it's really good to kind of enumerate the API endpoints that the server has. 23:21.010 --> 23:32.550 And the biggest issue is usually it doesn't correctly validate the client, which means once you're on the system, you perhaps can talk to a trusted service and do all sorts of nasty things. 23:32.550 --> 23:37.130 It's often application-specific based on the XPC server. 23:37.150 --> 23:39.810 But Apple has had all sorts of issues here. 23:39.810 --> 23:44.650 So, for example, the well-known root pipe vulnerability was a great example. 23:44.650 --> 23:48.710 There was an XPC service running on macOS as root. 23:48.830 --> 23:54.870 And it would, I think, create random arbitrary files and run arbitrary commands as root. 23:54.870 --> 23:56.650 And it didn't validate the client. 23:56.650 --> 24:03.650 So as soon as you were on the box, you could just send this XPC protocol request to this XPC service that was running. 24:03.650 --> 24:05.670 And it would be like, yeah, I'll run whatever you say. 24:05.670 --> 24:09.710 And so it was like the easiest, best privileged escalation vulnerability. 24:09.910 --> 24:13.610 So XPC, great protocol, Apple-specific. 24:13.890 --> 24:22.010 I always look at what kind of servers and applications, if they have an XPC interface, and start auditing those because oftentimes there are security issues there. 24:23.210 --> 24:25.690 That's your big blinking red light, huh? 24:25.690 --> 24:28.650 Yeah, like poke on that hard. 24:29.910 --> 24:33.170 Okay, so we have found ourselves in the last five minutes on this. 24:33.170 --> 24:37.670 If we have any more really good questions you want to drop in here, then please do. 24:37.670 --> 24:51.990 In the meantime, this is when I've taken to asking people if they have a general call to action, something you would like us to take away from the presentation that you've done, something that you'd like us all to consider and move forward with. 24:52.690 --> 25:03.390 Yeah, I mean, I think, you know, this is probably obvious to anyone listening here, but a lot of Mac users think that Macs are infallible. 25:03.390 --> 25:15.750 And this actually puts themselves at risk because, you know, a lot of Windows users will maybe participate in best cyber-safe practices, whatever that means. 25:15.750 --> 25:21.430 You know, don't download random apps, click random links in emails, run random applications. 25:21.430 --> 25:24.910 Whereas on macOS, people are prone to do that a little more. 25:24.930 --> 25:28.410 So, you know, just realizing Macs are just as hackable as Windows. 25:28.410 --> 25:33.750 It's an operating system that runs code, so just kind of stick with that. 25:33.790 --> 25:38.270 The other thing, and this is kind of a self-plug, but it's for free content, so I don't feel bad. 25:38.570 --> 25:45.330 In my presentation, I announced the free macOS book series I'm working on. 25:45.330 --> 25:54.950 So if you go to taomm.org, theartofmacmalware.org, I'm working on a free book about Mac malware analysis. 25:54.950 --> 26:00.610 So it talks a lot about infection vectors, these property lists, this XPC stuff. 26:00.610 --> 26:05.450 So if you're interested in, you know, Mac malware, vulnerability research, check it out. 26:05.450 --> 26:06.430 It's all free. 26:06.430 --> 26:10.110 The content, I've published the first part of the first volume. 26:10.110 --> 26:12.930 It's actually commentable on. 26:12.930 --> 26:19.910 So, you know, if you see an error or you want some input, you can just add a little comment, and I will add that into the content. 26:20.150 --> 26:21.470 And again, it's a free resource. 26:21.470 --> 26:32.410 It's basically trying to help provide more information for the community so that we can combat kind of the rising tide of Mac malware that's definitely coming. 26:32.930 --> 26:34.850 Well, that's something I can look forward to as well. 26:34.850 --> 26:35.370 So thank you. 26:35.370 --> 26:49.370 If you would be so kind as to drop the URL for that in the track one, and if you are willing to do so with any other contact information for you or a Twitter profile or something you want people to follow, that would be a good place for that. 26:49.750 --> 26:52.850 Yeah, and I'll put my Twitter, my DMs are open. 26:52.850 --> 26:54.530 Obviously, I'm very passionate about this. 26:54.530 --> 26:56.870 I love to nerd out, talk about this. 26:56.870 --> 27:00.630 So any questions, shoot me a DM, and we'll chat. 27:00.830 --> 27:01.870 Excellent. 27:02.390 --> 27:03.590 Thank you. 27:03.850 --> 27:09.210 We've gotten to the end of the questions in the live Q&A chat. 27:10.270 --> 27:20.250 I think that you've been a fantastic guest here, and we really appreciate your willingness to come and build a presentation and then spend some time with us in the Q&A. 27:20.990 --> 27:22.530 Yeah, thank you. 27:22.530 --> 27:24.610 Like I said, it's always an honor to talk at DEF CON. 27:24.610 --> 27:29.730 I just feel super appreciative to be able to share my research with just the DEF CON community. 27:29.730 --> 27:32.350 I mean, they're just the best. 27:33.010 --> 27:36.510 Well, we're the best because of the people who decide to come out and do this stuff. 27:36.510 --> 27:37.770 So thank you all. 27:39.130 --> 27:41.810 It seems like that's about all we have. 27:41.810 --> 27:47.730 So anybody who wants to do any follow-up on this one, you'll have some contact information showing up. 27:47.730 --> 27:50.850 And thank you all for showing up, and we'll do more later. 27:50.850 --> 27:51.410 Cool. 27:51.430 --> 27:52.310 See you guys later. 27:52.310 --> 27:53.250 Thanks for coming. 27:53.330 --> 27:54.070 Aloha.