Analysis by: Christopher Daniel So
ALIASES:

TrojanDropper:Win32/Boaxxe.G (Microsoft), Troj/Delp-F (Sophos)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • 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

Tamaño del archivo 125,952 bytes
Tipo de archivo DLL
Residente en memoria No
Fecha de recepción de las muestras iniciales 21 May 2011

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 registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{84B598F1-6B07-48B9-AB9A-861C01B1D71E}

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\{84B598F1-6B07-48B9-AB9A-861C01B1D71E}

It adds the following registry entries:

HKEY_CLASSES_ROOT\CLSID\{84B598F1-6B07-48B9-AB9A-861C01B1D71E}\
InprocServer32
(Default) = "{malware path and file name}"

  SOLUTION

Motor de exploración mínimo 8.900
Primer archivo de patrones de VSAPI 8.170.09
Primera fecha de publicación de patrones de VSAPI 21 May 2011

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Close all opened browser windows

Step 3

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects
    • {84B598F1-6B07-48B9-AB9A-861C01B1D71E}
  • In HKEY_CLASSES_ROOT\CLSID
    • {84B598F1-6B07-48B9-AB9A-861C01B1D71E}

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_BOAXXE.INC. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


Did this description help? Tell us how we did.