My presentation on how to use malware indicators of compromise to create rootcheck signatures for OSSEC. Explains different malware collection and analysis techniques.

1. Malware detection
with OSSEC
@santiagobassett

2. Setting up a malware lab
Collection Analysis
Detection
@santiagobassett

3. MW collection techniques
@santiagobassett
Honeypots
Web spiders - honeyclients
Malware crawlers

4. Honeypot
Dionaea: Low interaction honeypot that
emulates vulnerable network services.
https://github.com/rep/dionaea (written in C)
@santiagobassett
santiago@cuckoo:~$ nmap dionaea
Starting Nmap 6.00 ( http://nmap.org ) at 2014-09-07 21:04 PDT
Nmap scan report for dionaea (54.235.216.XXX)
Host is up (0.070s latency).
Not shown: 992 closed ports
PORT STATE SERVICE
21/tcp open ftp
42/tcp open nameserver
80/tcp open http
135/tcp open msrpc
443/tcp open https
445/tcp open microsoft-ds
1433/tcp open ms-sql-s
3306/tcp open mysql
Nmap done: 1 IP address (1 host up) scanned in 1.16 seconds

5. Honeypot results
• Captured 126 unique binaries in 3 months
• Highly detected by clamav (80%)
@santiagobassett
santiago@dionaea:/opt/dionaea/var/dionaea/binaries# clamscan *
022aeb126d2d80e683f7f2a3ee920874: Trojan.Spy-78857 FOUND
05800e1eb163994359e4c946d4a0fecb: Backdoor.Floder-3 FOUND
06267149140c0bc9ba51222c165f2d61: Worm.Autorun-7683 FOUND
0682f3dfbdab7c040ac9307c50792d0a: Trojan.Buzus-9369 FOUND
074b815d9ded01b516a62e3b739caa10: Win.Trojan.Agent-372503 FOUND
07fea379703307c5addc20e237cdd0f0: Win.Trojan.Jorik-1388 FOUND
09481313331ff5a8b8bfa4e25cbaa524: Worm.Autorun-7516 FOUND
0a9f1cd12f1b34ca71fa585e87e91c7d: OK
0b4c4078231ee36731080858187a49b8: Win.Trojan.Injector-8166 FOUND
0feae931ee71a495614f14f3c1d37246: Trojan.Mybot-5073 FOUND
10ec7cb47314a2c08decb25e53fedcfa: Trojan.Injector-558 FOUND
1205a52e42687c922aa4d3700d778398: Trojan.Kazy-1372 FOUND
12fb7332920a7797c2d02df29b57c640: Trojan.Spy-78857 FOUND
16b0357b804d9651d9057b61d78bee08: Win.Trojan.Agent-368816 FOUND
1a813b6ea08a47f2997e2e4215eba96b: WIN.Trojan.IRCBot-1225 FOUND
…
----------- SCAN SUMMARY -----------
Known viruses: 3517573
Engine version: 0.98.1
Scanned directories: 0
Scanned files: 126
Infected files: 101
Data scanned: 17.65 MB
Data read: 18.11 MB (ratio 0.97:1)
Time: 56.447 sec (0 m 56 s)

6. Honeyclient
Thug: Low interaction honeyclient, used to detect
drive-by-download attacks.
https://github.com/buffer/thug (Python)
Thug emulates:
• Core browser functionality
• ActiveX controls
• Browser plugins
@santiagobassett

7. Drive by download attack
@santiagobassett
http://urlquery.net/report.php?id=1410227505197

8. Honeyclient results
@santiagobassett
santiago@mwcollector:~/thug/src$ ./thug.py webgalleriet.no/
[2014-09-11 22:58:31] [HTTP] URL: http://www.webgalleriet.no/wordpress/wp-includes/js/comment-reply.
js?ver=20090102 (Status: 200, Referrer: http://www.webgalleriet.no/)
[2014-09-11 22:58:31] [HTTP] URL: http://www.webgalleriet.no/wordpress/wp-includes/js/comment-reply.
js?ver=20090102 (Content-type: application/javascript, MD5: d484fa08997df765852c6ad283ec52c6)
[2014-09-11 22:58:31] <iframe align="center" frameborder="no" height="2" name="Twitter" scrolling="auto"
src="http://168bet.com/cocs.html?j=1095012" width="2"></iframe>
[2014-09-11 22:58:31] [iframe redirection] http://www.webgalleriet.no/ ->
http://168bet.com/cocs.html?j=1095012
[2014-09-11 22:58:31] [URL Classifier] URL: http://168bet.com/cocs.html?j=1095012 (Rule: Redkit 1,
Classification: Landing page, Exploit Kit)

9. Malware crawlers
Retrieve files using malware tracking sites.
https://github.com/technoskald/maltrieve (Python)
https://code.google.com/p/malware-crawler/ (Python)
http://malc0de.com/rss http://www.malwareblacklist.com/mbl.xml http://www.malwaredomainlist.com/hostslist/mdl.xml
http://vxvault.siri-urz.net/URL_List.php http://urlquery.net/ http://support.clean-mx.de/clean-mx/xmlviruses.php
@santiagobassett

10. Malware tracking site

11. Malware crawlers results
• Captured 345 unique binaries in 15 minutes
• Poorly detected by clamav (16%)
@santiagobassett
santiago@mwcollector:~/binaries/maltrieve$
clamscan *
02d36dff08b63b123d2d2a36089e3d97: OK
03a6ac145099cf77bf5c7af127696687: OK
03e49fb415aacf9d2c90821ff0596024: OK
0568a72d4c5a2eb510207ca45b8d8799: OK
06ddb91e1d5f056590dfeef71a2da264: JS.Iframe-2
FOUND
074fbceca8fe84bae582a7a114b2ce94: HTML.Iframe-63
FOUND
0889504acc370f2adec7869b9bc5bc5c: OK
08d53833d032d71c1e7ffd3cddcd2a5e: JS.Iframe-2
FOUND
0ac790c459a0ef9bb4959321918a2d57: OK
0cc1c5c2ef510bd9f587abbc402d04a3: OK
0e3c692048a35c06ffe81a473ffd1d41: OK
136264a09b94bf8f08278b0045a84905: OK
13e78b2bab4a0ae9a3c2003d3f004dd1: JS.Obfus-31
FOUND
----------- SCAN SUMMARY ----------
-
Known viruses: 3517100
Engine version: 0.98.4
Scanned directories: 0
Scanned files: 235
Infected files: 38
Data scanned: 164.24 MB
Data read: 143.86 MB (ratio 1.14:1)
Time: 254.462 sec (4 m 14 s)

12. Malware database - Viper
Binary analysis and management framework.
https://github.com/botherder/viper (Python)
@santiagobassett

13. Static Analysis - Yara
Flexible, human-readable rules for identifying
malicious streams.
@santiagobassett
Can be used to analyze:
• files
• memory (volatility)
• network streams.
private rule APT1_RARSilent_EXE_PDF {
meta:
author = "AlienVault Labs"
info = "CommentCrew-threat-apt1"
strings:
$winrar1 = "WINRAR.SFX" wide ascii
$winrar2 = ";The comment below contains SFX
script commands" wide ascii
$winrar3 = "Silent=1" wide ascii
$str1 = /Setup=[sw"]+.(exe|pdf|doc)/
$str2 = "Steup="" wide ascii
condition:
all of ($winrar*) and 1 of ($str*)
}

14. Static Analysis - Yara
rule APT1_WEBC2_TABLE
{
viper > find name 3f2fda43121d888428b66717b984a7fb
+---+----------------------------------+-----------------------+----------------------------------+------+
| # | Name | Mime | MD5 | Tags |
+---+----------------------------------+-----------------------+----------------------------------+------+
| 1 | 3F2FDA43121D888428B66717B984A7FB | application/x-dosexec | 3f2fda43121d888428b66717b984a7fb | apt |
+---+----------------------------------+-----------------------+----------------------------------+------+
viper > open -l 1
[*] Session opened on
/home/santiago/viper/binaries/6/a/f/2/6af2116c4b59c69917e0e25efe4530a127830e2ed383ea91e0eebfa1cae4b78e
viper 3F2FDA43121D888428B66717B984A7FB > yara scan
[*] Scanning 3F2FDA43121D888428B66717B984A7FB
(6af2116c4b59c69917e0e25efe4530a127830e2ed383ea91e0eebfa1cae4b78e)
+------------------+--------+--------+----------------------------------+
| Rule | String | Offset | Content |
+------------------+--------+--------+----------------------------------+
| APT1_WEBC2_TABLE | $msg1 | 440032 | Fail To Execute The Command |
| APT1_WEBC2_TABLE | $msg2 | 440060 | Execute The Command Successfully |
| APT1_WEBC2_TABLE | $gif1 | 440100 | sdwefa.gif |
| APT1_WEBC2_TABLE | $gif1 | 440101 | dwefa.gif |
| APT1_WEBC2_TABLE | $gif1 | 440102 | wefa.gif |
| APT1_WEBC2_TABLE | $gif1 | 440103 | efa.gif |
| APT1_WEBC2_TABLE | $gif1 | 440104 | fa.gif |
| APT1_WEBC2_TABLE | $gif1 | 440105 | a.gif |
| APT1_WEBC2_TABLE | $gif2 | 440112 | GIF89 |
+------------------+--------+--------+----------------------------------+
@santiagobassett
meta:
author = "AlienVault Labs"
info = "CommentCrew-threat-apt1"
strings:
$msg1 = "Fail To Execute The
Command" wide ascii
$msg2 = "Execute The Command
Successfully" wide ascii
$gif1 = /w+.gif/
$gif2 = "GIF89" wide ascii
condition:
3 of them
}
viper 3F2FDA43121D888428B66717B984A7FB >
yara rules
+----+-----------------------------------+
| # | Path |
+----+-----------------------------------+
| 1 | data/yara/hangover.yara |
| 2 | data/yara/citizenlab.yara |
| 3 | data/yara/APT_NGO_wuaclt_PDF.yara |
| 4 | data/yara/kins.yara |
| 5 | data/yara/themask.yara |
| 6 | data/yara/vmdetect.yara |
| 7 | data/yara/index.yara |
| 8 | data/yara/GeorBotBinary.yara |
| 9 | data/yara/leverage.yar |
| 10 | data/yara/apt1.yara |
| 11 | data/yara/GeorBotMemory.yara |
| 12 | data/yara/rats.yara |
| 13 | data/yara/embedded.yara |
| 14 | data/yara/urausy_skypedat.yar |
| 15 | data/yara/fpu.yara |
+----+-----------------------------------+

15. Static Analysis – Trojan Dropper
viper 0A37D49E798F50C8F1010D5CFDE0E851 > virustotal
[*] VirusTotal Report:
+----------------------+----------------------------------------------
+
| Antivirus | Signature
|
+----------------------+----------------------------------------------
+
| nProtect | Trojan.Downloader.JKVR
|
| McAfee | Artemis!0A37D49E798F
|
| K7GW | Trojan-Downloader
|
| NANO-Antivirus | Trojan.Win32.Agent.hbmsz
|
| Symantec | Downloader
|
| TotalDefense | Win32/FakeDoc_i
|
| TrendMicro-HouseCall | TROJ_DLOADER.VTG
|
| Avast | Win32:Trojan-gen
|
| ClamAV | Trojan.Downloader-83571
|
| Kaspersky | Trojan-Downloader.Win32.Agent.thb
|
| BitDefender | Trojan.Downloader.JKVR
|
| Agnitum | Trojan.DL.Agent!virRS0ijj7k
|
| Emsisoft | Trojan.Downloader.JKVR (B)
|
| Comodo | TrojWare.Win32.TrojanDownloader.Agent.thb_30
|
| F-Secure | Trojan.Downloader.JKVR
|
| TrendMicro | TROJ_DLOADER.VTG
|
| McAfee-GW-Edition | Artemis!0A37D49E798F
|
| Sophos | Troj/DwnLdr-IYR
|
| Jiangmin | TrojanDownloader.Agent.boly
|
| Antiy-AVL | Trojan/Win32.Agent.gen
|
| Microsoft | TrojanDownloader:Win32/Pingbed.A
|
| Commtouch | W32/Downloader.NIHT-8726
|
| AhnLab-V3 | Dropper/Malware.101512
@santiagobassett
viper 0A37D49E798F50C8F1010D5CFDE0E851 > pe sections
[*] PE Sections:
+--------+---------+-------------+-------------+---------------+
| Name | RVA | VirtualSize | RawDataSize | Entropy |
+--------+---------+-------------+-------------+---------------+
| .text | 0x1000 | 0xbe8f | 49152 | 6.52204488284 |
| .rdata | 0xd000 | 0x1855 | 6656 | 5.17849300065 |
| .data | 0xf000 | 0x19cb8 | 512 | 1.31023024266 |
| .CRT | 0x29000 | 0x10 | 512 | 0.21310128451 |
| .rsrc | 0x2a000 | 0x7fd8 | 32768 | 5.79943302325 |
+--------+---------+-------------+-------------+---------------+
viper 0A37D49E798F50C8F1010D5CFDE0E851 > pe imports
...
[*] DLL: ADVAPI32.dll
- 0x40d000: RegCloseKey
- 0x40d004: RegOpenKeyExA
- 0x40d008: RegQueryValueExA
- 0x40d00c: RegCreateKeyExA
- 0x40d010: RegSetValueExA
...
viper 0A37D49E798F50C8F1010D5CFDE0E851 > pe compiletime
[*] Compile Time: 2010-03-14 23:27:58
viper 0A37D49E798F50C8F1010D5CFDE0E851 > yara scan
[*] Scanning 0A37D49E798F50C8F1010D5CFDE0E851
(dbf0436908c9d900e69ea2a108f08061786d299b511265b78620a4401361084b)
viper 0A37D49E798F50C8F1010D5CFDE0E851 > fuzzy
[*] 1 relevant matches found
+-------+----------------------------------+------------------------------------------------------------------+
| Score | Name | SHA256 |
+-------+----------------------------------+------------------------------------------------------------------+
| 68% | 003EE3D21DF82975337AE976F8BA67CC | 2803fba5fbe908f6151597c2a387caef8f00a5f0f194bfc6b4d9f89026d53621 |
+-------+----------------------------------+------------------------------------------------------------------+

16. Fuzzy hash match info
@santiagobassett

17. Dynamic Analysis - Cuckoo
Automated malware analysis. Runs binary files in
virtual machines to study their behavior.
@santiagobassett
• Traces Win32 API calls
• Files created, deleted and downloaded
• Memory dumps of malicious processes
• Network traffic pcaps
Integrated with yara, virustotal and volatility among
other tools. Supports Virtualbox KVM and Vmware.

18. Dynamic Analysis – Trojan Dropper
@santiagobassett

19. Behavioral Analysis – Filesystem
@santiagobassett

20. Behavioral Analysis - Filesystem
@santiagobassett

21. Behavioral Analysis – Network
@santiagobassett

22. Behavioral Analysis – Network
@santiagobassett

23. Behavioral Analysis - Network
santiago@cuckoo:~/Cuckoo/cuckoo/storage/analyses/34$ sudo tcpdump -s 0 -XX -AA -nn -r dump.pcap | grep -A
4 63.233.155.6
reading from file dump.pcap, link-type EN10MB (Ethernet)
23:32:20.655808 IP 8.8.8.8.53 > 192.168.56.103.63943: 53551 1/0/0 A 63.233.155.6 (50)
@santiagobassett
0x0000: 0800 2723 f165 0a00 2700 0000 0800 4500 ..'#.e..'.....E.
0x0010: 004e eca8 0000 2d11 97d7 0808 0808 c0a8 .N....-.........
0x0020: 3867 0035 f9c7 003a ef52 d12f 8180 0001 8g.5...:.R./....
0x0030: 0001 0000 0000 0377 7777 0867 6172 7968 .......www.garyh
--
23:32:20.662766 IP 192.168.56.103.49166 > 63.233.155.6.80: Flags [S], seq 2615622815, win 8192, options
[mss 1460,nop,wscale 2,nop,nop,sackOK], length 0
0x0000: 0a00 2700 0000 0800 2723 f165 0800 4500 ..'.....'#.e..E.
0x0010: 0034 10ab 4000 8006 161a c0a8 3867 3fe9 .4..@.......8g?.
0x0020: 9b06 c00e 0050 9be7 3c9f 0000 0000 8002 .....P..<.......
0x0030: 2000 e231 0000 0204 05b4 0103 0302 0101 ...1............
--
23:32:23.663174 IP 192.168.56.103.49166 > 63.233.155.6.80: Flags [S], seq 2615622815, win 8192, options
[mss 1460,nop,wscale 2,nop,nop,sackOK], length 0
0x0000: 0a00 2700 0000 0800 2723 f165 0800 4500 ..'.....'#.e..E.
0x0010: 0034 10c2 4000 8006 1603 c0a8 3867 3fe9 .4..@.......8g?.
0x0020: 9b06 c00e 0050 9be7 3c9f 0000 0000 8002 .....P..<.......
0x0030: 2000 e231 0000 0204 05b4 0103 0302 0101 ...1............
--
23:32:29.661778 IP 192.168.56.103.49166 > 63.233.155.6.80: Flags [S], seq 2615622815, win 8192, options
[mss 1460,nop,nop,sackOK], length 0
0x0000: 0a00 2700 0000 0800 2723 f165 0800 4500 ..'.....'#.e..E.
0x0010: 0030 10dc 4000 8006 15ed c0a8 3867 3fe9 .0..@.......8g?.
0x0020: 9b06 c00e 0050 9be7 3c9f 0000 0000 7002 .....P..<.....p.
0x0030: 2000 f63a 0000 0204 05b4 0101 0402 ...:..........

24. Behavioral Analysis – Registry
@santiagobassett

25. Memory Analysis - Volatility
santiago@cuckoo:~/Cuckoo/cuckoo/storage/analyses/34$ vol.py psxview --profile=Win7SP1x86 -f memory.dmp
Volatility Foundation Volatility Framework 2.4
Offset(P) Name PID pslist psscan thrdproc pspcid csrss session deskthrd
---------- -------------------- ------ ------ ------ -------- ------ ----- ------- --------
0x7b6fa500 audiodg.exe 960 True False True True True True True
0x7b7afd40 sppsvc.exe 1780 True False True True True True True
0x779fb808 svchost.exe 724 True False True True True True True
0x7b7be710 svchost.exe 1892 True False True True True True True
0x7c4ea7d8 VBoxService.ex 624 True False True True True True True
0x7b6f4030 svchost.exe 900 True False True True True True True
0x7b7bb618 svchost.exe 3376 True False True True True True True
0x7cd99a58 AcroRD32.exe 3080 True False True True True True True
0x7b4fa030 SearchIndexer. 360 True False True True True True True
0x7b94a858 taskhost.exe 2920 True False True True True True True
…
santiago@cuckoo:~$ strings
3080.dmp | grep -i garyhart
www.garyhart.com
w.garyhart.com
w.garyhart.com
w.garyhart.com
www.garyhart.com
st: www.garyhart.com
w.garyhart.com
tp://www.garyhart.com/nfuse.htm
tp://www.garyhart.com/nfuse.htm
tp://www.garyhart.com/nfuse.htm
tp://www.garyhart.com/nfuse.htm
tp://www.garyhart.com/nfuse.htm
tp://www.garyhart.com/nfuse.htm
www.garyhart.com
http://www.garyhart.com/nfuse.htm
santiago@cuckoo:~/Cuckoo/cuckoo/storage/analyses/34$ vol.py memdump --profile=Win7SP1x86 -f memory.dmp -D
./ -p 3080
Volatility Foundation Volatility Framework 2.4
************************************************************************
Writing AcroRD32.exe [ 3080] to 3080.dmp
@santiagobassett

26. Memory Analysis - Yara
santiago@cuckoo:~/Cuckoo/cuckoo/storage/analyses/34$ yara /home/santiago/viper/data/yara/apt1.yara 3080.dmp
APT1_WEBC2_UGX 3080.dmp
@santiagobassett
rule APT1_WEBC2_UGX
{
meta:
author = "AlienVault Labs"
info = "CommentCrew-threat-apt1”
strings:
$persis =
"SOFTWAREMICROSOFTWINDOWSCURRENTVERSIONRUN"
wide ascii
$exe = "DefWatch.exe" wide ascii
$html = "index1.html" wide ascii
$cmd1 = "!@#tiuq#@!" wide ascii
$cmd2 = "!@#dmc#@!" wide ascii
$cmd3 = "!@#troppusnu#@!" wide ascii
condition:
3 of them
}

27. OSSEC - Rootcheck
Used for rootkits and malware detection. It can be
used to:
• Look for suspicious files.
• Inspect files and registry keys for common
rootkits/malware entries.
• Look for hidden processes and network ports.
@santiagobassett

28. OSSEC – Rule for Trojan Dropper
[Trojan Dropper] [all] [0A37D49E798F50C8F1010D5CFDE0E851]
f:C:UsersIEUserAppDataLocalTempAcroRD32.exe;
r:HKEY_USERSS-1-5-21-3463664321-2923530833-3546627382-1000
SoftwareMicrosoftWindowsCurrentVersionRun -> Acroread
-> r:AcroRD32.exe;
@santiagobassett
p:r:AcroRD32.exe;
/var/ossec/etc/shared/win_malware_rcl.txt

29. OSSEC – Alert for Trojan Dropper
alienvault:/var/ossec/bin# ./rootcheck_control -L -i 001
Policy and auditing events for agent 'Windows7 (001) -
172.16.126.134':
@santiagobassett
Resolved events:
** No entries found.
Last scan: 2014 Sep 12 18:54:24
Windows Audit: Null sessions allowed.
Windows Malware: Trojan Dropper.
File: C:UsersIEUserAppDataLocalTempAcroRD32.exe.
Reference: 0A37D49E798F50C8F1010D5CFDE0E851 .

30. Demo – Alert for Trojan Dropper
@santiagobassett

31. Future Work
• Use/create Cuckoo signatures to identify different
malware patterns (droppers, downloaders, trojans,
rootkits, …)
• Create Cuckoo reporting module to report (JSON)
on those patterns that OSSEC can detect.
• Python tool to parse module output and generate
rootcheck rules.
• Add/improve OSSEC malware detection capabilities.
@santiagobassett

32. Thank you!
santiago@alienvault.com
@santiagobassett