1 1 00:00:00,549 --> 00:00:02,490 IAM Auditing. 2 2 00:00:02,490 --> 00:00:03,810 In this lesson, we're going to talk 3 3 00:00:03,810 --> 00:00:06,330 about auditing and monitoring and logging. 4 4 00:00:06,330 --> 00:00:08,670 First, let's talk about IAM auditing 5 5 00:00:08,670 --> 00:00:11,700 because IAM auditing is necessary for us to use 6 6 00:00:11,700 --> 00:00:14,460 if we want to detect compromises of legitimate accounts 7 7 00:00:14,460 --> 00:00:17,910 any kind of rogue account use or an insider threat. 8 8 00:00:17,910 --> 00:00:20,940 The idea with IAM auditing is to look through our systems 9 9 00:00:20,940 --> 00:00:22,950 to see if there's anything bad happening, 10 10 00:00:22,950 --> 00:00:24,630 and one of the best ways to do that is 11 11 00:00:24,630 --> 00:00:26,610 by monitoring and logging. 12 12 00:00:26,610 --> 00:00:28,650 Now, one of the most key logs we're going to be looking 13 13 00:00:28,650 --> 00:00:30,360 at is our audit logs. 14 14 00:00:30,360 --> 00:00:32,850 Audit logs contain a log of all file access 15 15 00:00:32,850 --> 00:00:35,550 and authentications within a network-based operating system, 16 16 00:00:35,550 --> 00:00:37,860 an application or a service. 17 17 00:00:37,860 --> 00:00:39,480 As we go through our audit logs, 18 18 00:00:39,480 --> 00:00:42,150 we're going to be accounting for all of our user actions. 19 19 00:00:42,150 --> 00:00:42,983 As we look through that 20 20 00:00:42,983 --> 00:00:45,180 and we see which users did which things, 21 21 00:00:45,180 --> 00:00:46,950 were they supposed to be able to do those things 22 22 00:00:46,950 --> 00:00:49,020 and why were they doing those things? 23 23 00:00:49,020 --> 00:00:51,030 As we look through that, we can figure that out. 24 24 00:00:51,030 --> 00:00:51,960 That would help us determine 25 25 00:00:51,960 --> 00:00:54,330 if there was some rogue account use going on. 26 26 00:00:54,330 --> 00:00:56,730 Also, we're going to use this to detect intrusions 27 27 00:00:56,730 --> 00:00:58,230 or attempted intrusions. 28 28 00:00:58,230 --> 00:01:00,270 For instance, if I look in there and I see 29 29 00:01:00,270 --> 00:01:01,200 that somebody tried logging 30 30 00:01:01,200 --> 00:01:04,080 into the same account multiple times and failed 31 31 00:01:04,080 --> 00:01:05,160 that could be an indication 32 32 00:01:05,160 --> 00:01:06,810 that somebody's trying to break into that account. 33 33 00:01:06,810 --> 00:01:09,720 That would be an attempted intrusion or it's an indication 34 34 00:01:09,720 --> 00:01:11,340 that somebody just forgot their password. 35 35 00:01:11,340 --> 00:01:12,840 Now again, we're going to have to look at these 36 36 00:01:12,840 --> 00:01:15,690 and make the intelligent guess based on what we're seeing. 37 37 00:01:15,690 --> 00:01:17,520 If I look through my audit logs and I see 38 38 00:01:17,520 --> 00:01:20,130 that somebody tried logging in with A and then AA 39 39 00:01:20,130 --> 00:01:23,640 and then AB, and then AC, what does that look like to you? 40 40 00:01:23,640 --> 00:01:25,830 To me, it looks like a brute force login attempt 41 41 00:01:25,830 --> 00:01:27,540 and so I would want to go and look at that, 42 42 00:01:27,540 --> 00:01:28,860 turn that access off 43 43 00:01:28,860 --> 00:01:30,750 and then go into a further investigation. 44 44 00:01:30,750 --> 00:01:32,340 Now, one of the things we have to worry about 45 45 00:01:32,340 --> 00:01:35,130 here is logging and logging can be a really good thing 46 46 00:01:35,130 --> 00:01:37,440 but it can also be a really dangerous thing for us. 47 47 00:01:37,440 --> 00:01:39,120 Now, why would logging be dangerous? 48 48 00:01:39,120 --> 00:01:41,670 Because we could become buried in logs. 49 49 00:01:41,670 --> 00:01:43,620 Obviously, the more events that are logged, 50 50 00:01:43,620 --> 00:01:44,880 the more difficult it's going to be 51 51 00:01:44,880 --> 00:01:47,490 for us to analyze and interpret those logs. 52 52 00:01:47,490 --> 00:01:49,890 Therefore, it's important for us as cybersecurity analysts 53 53 00:01:49,890 --> 00:01:52,770 for us to choose what to log and how much to log 54 54 00:01:52,770 --> 00:01:54,690 and we have to do this carefully. 55 55 00:01:54,690 --> 00:01:57,450 The other challenge with logs is that they get overwritten. 56 56 00:01:57,450 --> 00:02:00,330 When logs reach their maximum allocated file size, 57 57 00:02:00,330 --> 00:02:02,760 they're going to actually start overwriting the older logs 58 58 00:02:02,760 --> 00:02:05,160 so you need to make sure that you have a way 59 59 00:02:05,160 --> 00:02:06,870 to back up those logs and be able 60 60 00:02:06,870 --> 00:02:08,520 to look at them in the future. 61 61 00:02:08,520 --> 00:02:11,310 For example, we talked earlier about intrusions. 62 62 00:02:11,310 --> 00:02:14,460 How long does it take before the average intrusion is found? 63 63 00:02:14,460 --> 00:02:17,040 Over half of the time it took months. 64 64 00:02:17,040 --> 00:02:18,630 So if you have logs that are being overwritten 65 65 00:02:18,630 --> 00:02:21,450 every seven days, you'll never be able to find it. 66 66 00:02:21,450 --> 00:02:23,670 So you need to be able to think about that as well 67 67 00:02:23,670 --> 00:02:26,040 as you think about what your maximum allocatable size is 68 68 00:02:26,040 --> 00:02:27,780 or if you're going to offload those logs 69 69 00:02:27,780 --> 00:02:30,300 to another system where you can store them for longer. 70 70 00:02:30,300 --> 00:02:31,260 Another thing you have to think about 71 71 00:02:31,260 --> 00:02:32,520 when you're storing these logs is 72 72 00:02:32,520 --> 00:02:34,050 how are you going to keep them secure? 73 73 00:02:34,050 --> 00:02:35,250 Are you going to encrypt them? 74 74 00:02:35,250 --> 00:02:37,320 Are you going to make sure there's confidentiality to them 75 75 00:02:37,320 --> 00:02:40,080 and are you going to hash them to make sure there's integrity? 76 76 00:02:40,080 --> 00:02:42,840 You want to make sure that these logs aren't being modified 77 77 00:02:42,840 --> 00:02:45,270 because an attacker, when they break into your system, 78 78 00:02:45,270 --> 00:02:47,490 one of the things they want to do is cover their tracks 79 79 00:02:47,490 --> 00:02:50,220 and they will do that by modifying your logs. 80 80 00:02:50,220 --> 00:02:52,680 Now, when you start determining what to log 81 81 00:02:52,680 --> 00:02:55,590 this can be a challenge for a lot of security personnel. 82 82 00:02:55,590 --> 00:02:58,200 Most people just say, "I'm going to log everything," 83 83 00:02:58,200 --> 00:03:00,690 but that can be gigabytes of information every hour 84 84 00:03:00,690 --> 00:03:02,820 or every day, and you might not have enough data 85 85 00:03:02,820 --> 00:03:04,440 to store it all on your system, 86 86 00:03:04,440 --> 00:03:07,050 so you have to think about what you want to store. 87 87 00:03:07,050 --> 00:03:08,280 Now, to figure this out, 88 88 00:03:08,280 --> 00:03:11,400 you should take a look at the audit policy recommendations. 89 89 00:03:11,400 --> 00:03:13,710 This is a document on Microsoft's website 90 90 00:03:13,710 --> 00:03:15,030 and it'll give you some recommendations 91 91 00:03:15,030 --> 00:03:18,120 on how they say you should configure your audit policy. 92 92 00:03:18,120 --> 00:03:19,800 Some typical categories that are covered 93 93 00:03:19,800 --> 00:03:21,330 underneath these recommendations are things 94 94 00:03:21,330 --> 00:03:23,400 like the account log on and management events, 95 95 00:03:23,400 --> 00:03:25,290 and how many of those you should be capturing. 96 96 00:03:25,290 --> 00:03:28,050 The process creation, the object access, 97 97 00:03:28,050 --> 00:03:30,600 things like file systems and file shares, 98 98 00:03:30,600 --> 00:03:32,520 things like changes to your audit policy 99 99 00:03:32,520 --> 00:03:35,100 or changes to system security and integrity 100 100 00:03:35,100 --> 00:03:37,740 like for instance, if somebody turns on or off a firewall, 101 101 00:03:37,740 --> 00:03:40,290 on or off an antivirus, and things like that. 102 102 00:03:40,290 --> 00:03:41,850 All of these are things you should consider 103 103 00:03:41,850 --> 00:03:43,530 as you're determining what to log 104 104 00:03:43,530 --> 00:03:45,960 because these are some of the big rocks. 105 105 00:03:45,960 --> 00:03:48,150 Now, if you want to configure all of this, again, 106 106 00:03:48,150 --> 00:03:50,010 you can refer to that Microsoft document 107 107 00:03:50,010 --> 00:03:51,180 but essentially you're going to go 108 108 00:03:51,180 --> 00:03:52,800 into your group policy object 109 109 00:03:52,800 --> 00:03:54,900 and you're going to go in there and configure these things. 110 110 00:03:54,900 --> 00:03:56,820 Either enable them or disable them based 111 111 00:03:56,820 --> 00:03:59,460 on how much you want to log and what you want to log. 112 112 00:03:59,460 --> 00:04:01,830 Now again, the reason logging is so important is 113 113 00:04:01,830 --> 00:04:04,110 because it is the primary method we use 114 114 00:04:04,110 --> 00:04:06,720 to uncover account access violations. 115 115 00:04:06,720 --> 00:04:08,130 This is known as a log review. 116 116 00:04:08,130 --> 00:04:10,140 We're going to go through and look at these logs. 117 117 00:04:10,140 --> 00:04:11,250 If you're logging everything 118 118 00:04:11,250 --> 00:04:14,010 but you never look at the logs, they're worthless to you. 119 119 00:04:14,010 --> 00:04:15,090 Logs are only good 120 120 00:04:15,090 --> 00:04:17,460 if you open them up and actually look at them. 121 121 00:04:17,460 --> 00:04:19,770 Now, what are you going to be looking for in this log review? 122 122 00:04:19,770 --> 00:04:22,710 Well, multiple consecutive authentication failures, 123 123 00:04:22,710 --> 00:04:23,730 that's a good indication 124 124 00:04:23,730 --> 00:04:25,770 that somebody's trying to break into your network. 125 125 00:04:25,770 --> 00:04:27,300 You might look for unscheduled changes 126 126 00:04:27,300 --> 00:04:28,860 to a system's configuration. 127 127 00:04:28,860 --> 00:04:31,560 That might tell you that they're infected with malware. 128 128 00:04:31,560 --> 00:04:34,260 You might look at sequencing errors or gaps in logs. 129 129 00:04:34,260 --> 00:04:36,570 This can tell you, you have a modification problem. 130 130 00:04:36,570 --> 00:04:37,950 Somebody might have broken into your system 131 131 00:04:37,950 --> 00:04:41,040 and deleted some of the logs, or they modified the logs. 132 132 00:04:41,040 --> 00:04:43,590 All of these are things you have to worry about. 133 133 00:04:43,590 --> 00:04:44,880 Now, another thing you need to worry 134 134 00:04:44,880 --> 00:04:47,220 about is doing a manual review. 135 135 00:04:47,220 --> 00:04:50,220 Now, a manual review helps you look at your user accounts 136 136 00:04:50,220 --> 00:04:52,560 and make sure they actually have the right permissions. 137 137 00:04:52,560 --> 00:04:53,730 Why do you need to do this? 138 138 00:04:53,730 --> 00:04:55,890 Well, because in every company. 139 139 00:04:55,890 --> 00:04:58,320 people get hired and people get fired 140 140 00:04:58,320 --> 00:05:00,360 and as people are hired, they're given permissions. 141 141 00:05:00,360 --> 00:05:02,700 When they're fired, they should be losing permissions 142 142 00:05:02,700 --> 00:05:04,950 and if they move even jobs within the company, 143 143 00:05:04,950 --> 00:05:06,630 they should have different permission levels based 144 144 00:05:06,630 --> 00:05:07,890 on the job they have. 145 145 00:05:07,890 --> 00:05:10,410 So doing a manual review will make sure 146 146 00:05:10,410 --> 00:05:13,080 that those permissions are accurate for those users. 147 147 00:05:13,080 --> 00:05:15,030 This is an important thing and another reason 148 148 00:05:15,030 --> 00:05:17,010 why we'd like to put people in and out of groups 149 149 00:05:17,010 --> 00:05:18,030 to give them permission 150 150 00:05:18,030 --> 00:05:19,710 as opposed to giving people permissions 151 151 00:05:19,710 --> 00:05:22,680 directly on different file shares or different services. 152 152 00:05:22,680 --> 00:05:24,660 It's easier to take them and remove them from groups 153 153 00:05:24,660 --> 00:05:26,400 than it is to find every single place 154 154 00:05:26,400 --> 00:05:27,870 that they have been given permission. 155 155 00:05:27,870 --> 00:05:29,460 So keep that in mind and try to use 156 156 00:05:29,460 --> 00:05:32,280 role-based authentication as you set up your systems. 157 157 00:05:32,280 --> 00:05:34,500 Now, the other thing we're going to do is a re-certification 158 158 00:05:34,500 --> 00:05:36,480 and this is part of our manual review. 159 159 00:05:36,480 --> 00:05:39,060 A re-certification essentially is a manual review 160 160 00:05:39,060 --> 00:05:41,760 of all the accounts, the permissions, the configurations 161 161 00:05:41,760 --> 00:05:43,590 and the clearance levels, and you'll do this 162 162 00:05:43,590 --> 00:05:46,890 at a given interval that might be monthly, quarterly 163 163 00:05:46,890 --> 00:05:49,710 every six months, every year, every five years. 164 164 00:05:49,710 --> 00:05:50,730 I don't care what it is. 165 165 00:05:50,730 --> 00:05:53,460 That's for you and your organization to determine based 166 166 00:05:53,460 --> 00:05:54,900 on your risk appetite. 167 167 00:05:54,900 --> 00:05:57,810 In my organization, we do this once a year. 168 168 00:05:57,810 --> 00:06:00,090 Now that's a pretty long time for most organizations 169 169 00:06:00,090 --> 00:06:01,680 but we have a small staff 170 170 00:06:01,680 --> 00:06:04,740 and we don't have people hiring and firing very commonly 171 171 00:06:04,740 --> 00:06:06,870 so for us, a recertification isn't something 172 172 00:06:06,870 --> 00:06:08,640 that takes a big priority based 173 173 00:06:08,640 --> 00:06:10,773 on our risk appetite and our risk posture.