Analysis by: Jaime Benigno Reyes
ALIASES:

Trojan:Win32/Vundo.gen!AI (Microsoft); Packed.Win32.Mondera.b (Kaspersky); Trojan.Vundo (Symantec); Vundo.gen.o (McAfee)

 PLATFORM:

Windows

 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: 92,725 bytes
File Type: DLL
Memory Resident: No
Initial Samples Received Date: 08 Apr 2009

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.

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
CPM{8 random alphanumeric characters} = "Rundll32.exe "{malware path}\{malware name}",a"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}

HKEY_CLASSES_ROOT\CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\
InprocServer32

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\InprocServer32

It adds the following registry entries:

HKEY_CLASSES_ROOT\CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\
InprocServer32
@ = "{malware path}\{malware name}"

HKEY_CLASSES_ROOT\CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\
InprocServer32
ThreadingModel = "Both"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\InprocServer32
@ = "{malware path}\{malware name}"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}\InprocServer32
ThreadingModel = "Both"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
SharedTaskScheduler
{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4} = "STS"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\ShellServiceObjectDelayLoad
SSODL = "{EC43E3FD-5C60-46a6-97D7-E0B85DBDD6C4}"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Windows
LoadAppInit_DLLs = "1"