Analysis by: Adrian Cofreros

ALIASES:

a variant of Win32/Injector.AKKG trojan(NOD32),TR/Agent.598016(Antivir)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

  TECHNICAL DETAILS

File Size: 647,168 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 03 Aug 2013

Arrival Details

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

Installation

This Trojan drops the following files:

  • %User Temp%\UuU.uUu
  • %User Temp%\XxX.xXx
  • %Application Data%\logs.dat

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It drops the following copies of itself into the affected system:

  • %Windows%\Windows.dll - for windows XP
  • %Application Data%\Windows.dll - for windows 7

(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer\Run
ctfmon = "%Windows%\Windows.dll"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
ctfmon = "%Windows%\Windows.dll"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Windows = "{path and filename of dropped copy}"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\WindowsNT

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{1221254T-0T64-181A-O2IW-A810J2EET031} -for windows XP

HKEY_CURRENT_USER\Software\Classes\
VirtualStore\MACHINE\SOFTWARE\
Microsoft\Active Setup\Installed Components\
{1221254T-0T64-181A-O2IW-A810J2EET031} - for Windows 7

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{1221254T-0T64-181A-O2IW-A810J2EET031} -for windows XP
StubPath = "%Windows%\Windows.dll"

HKEY_CURRENT_USER\Software\Classes\
VirtualStore\MACHINE\SOFTWARE\
Microsoft\Active Setup\Installed Components\
{1221254T-0T64-181A-O2IW-A810J2EET031} -for Windows 7
StubPath = "%Application Data%\Windows.dll Restart"

HKEY_CURRENT_USER\Software\WindowsNT
FirstExecution = "{date} -- {time}"

HKEY_CURRENT_USER\Software\WindowsNT
NewIdentification = "WindowsNT"

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}computer.no-ip.org