Submission Summary:

• Submission details:
• Submission received: 5 October 2012, 16:51:03
• Processing time: 7 min 32 sec
• Submitted sample:
• File MD5: 0x82F8FEEF6B81ECDD854779739C841623
• File SHA-1: 0x73655F0F257CA434AAB26FD6561CEA6B381AF5BB
• Filesize: 166,490 bytes
• Alias:
• Backdoor.Win32.Ruskill.feo [Kaspersky Lab]
• Generic Dropper!1pw [McAfee]
• Mal/Generic-L [Sophos]
• Worm:Win32/Dorkbot.A [Microsoft]

Technical Details:

Possible Security Risk

• Attention! The following threat category was identified:

Threat Category	Description
	A malicious backdoor trojan that runs in the background and allows remote access to the compromised system

File System Modifications

• The following file was created in the system:

#	Filename(s)	File Size	File Hash	Alias
1	%AppData%\Wcxaxw.exe [file and pathname of the sample #1]	166,490 bytes	MD5: 0x82F8FEEF6B81ECDD854779739C841623 SHA-1: 0x73655F0F257CA434AAB26FD6561CEA6B381AF5BB	Backdoor.Win32.Ruskill.feo [Kaspersky Lab] Generic Dropper!1pw [McAfee] Mal/Generic-L [Sophos] Worm:Win32/Dorkbot.A [Microsoft]

• Note:
• %AppData% is a variable that refers to the file system directory that serves as a common repository for application-specific data. A typical path is C:\Documents and Settings\[UserName]\Application Data.

Memory Modifications

• There were new memory pages created in the address space of the system process(es):

Process Name	Process Filename	Allocated Size
services.exe	%System%\services.exe	319,488 bytes
svchost.exe	%System%\svchost.exe	319,488 bytes
svchost.exe	%System%\svchost.exe	319,488 bytes
svchost.exe	%System%\svchost.exe	319,488 bytes
svchost.exe	%System%\svchost.exe	319,488 bytes
svchost.exe	%System%\svchost.exe	319,488 bytes
alg.exe	%System%\alg.exe	319,488 bytes

• Notes:
• %System% is a variable that refers to the System folder. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

Registry Modifications

• The newly created Registry Value is:
• [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run]
• Wcxaxw = "%AppData%\Wcxaxw.exe"

so that Wcxaxw.exe runs every time Windows starts

Other details

• To mark the presence in the system, the following Mutex object was created:
• 1fed6b9a-Mutex