JS_NEMUCOD.JDENC

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It does not have any propagation routine.

It does not have any backdoor routine.

It executes downloaded files whose malicious routines are exhibited by the affected system. As of this writing, the said sites are inaccessible.

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Download Routine

This Trojan connects to the following website(s) to download and execute a malicious file:

• http://{BLOCKED}g5g.{BLOCKED}ge.t-online.de/HJghjt872?pwnLdlVgCm=HfTIWnVJgw
• http://{BLOCKED}393.{BLOCKED}s.easily.co.uk/HJghjt872?pwnLdlVgCm=HfTIWnVJgw
• http://{BLOCKED}ker.{BLOCKED}e.de/HJghjt872?pwnLdlVgCm=HfTIWnVJgw

It saves the files it downloads using the following names:

• %User Temp%uaekujazTi1 <- encrypted download file
• %User Temp%uaekujazTi1.dll
• %User Temp%uaekujazTi2 <- encrypted download file
• %User Temp%uaekujazTi2.dll
• %User Temp%uaekujazTi3 <- encrypted download file
• %User Temp%uaekujazTi3.dll

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It executes downloaded files :

• %User Temp%uaekujazTi1.dll
• %User Temp%uaekujazTi2.dll
• %User Temp%uaekujazTi3.dll

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

As of this writing, the said sites are inaccessible.

NOTES:

It does not have rootkit capabilities.

It does not exploit any vulnerability.