Analysis by: Sabrina Lei Sioting
 Modified by: Michael Cabel
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • 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: 63,720,136 bytes
File Type: EXE
File Compression: SFX
Memory Resident: No
Initial Samples Received Date: 19 Jul 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.

NOTES:
These are legitimate installers of the following applications whose code has been altered by another malware:

  • Microsoft SQL 2005 Server Express Edition
  • Microsoft Office 2003 Pro
It connect to remote sites to download the following files:
  • http://{BLOCKED}t.{BLOCKED}ndme.com:808/sink.exe
However, as of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 8.298.09
FIRST VSAPI PATTERN DATE: 19 Jul 2011
VSAPI OPR PATTERN File: 8.299.00
VSAPI OPR PATTERN Date: 19 Jul 2011

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOADER.YHW. 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.