Analysis by: Karl Dominguez
 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Trojan has received attention from independent media sources and/or other security firms.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

It connects to certain websites to send and receive information. It deletes itself after execution.

  TECHNICAL DETAILS

File Size: 96,768 bytes
File Type: PE
Memory Resident: Yes
Initial Samples Received Date: 31 Aug 2010
Payload: Connects to URLs/Ips, Modifies files

Arrival Details

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

It may be downloaded from the following remote sites:

  • http://{BLOCKED}mentconsulting.com/tweetdeck-08302010-update.exe

Installation

This Trojan drops the following component file(s):

  • \?\globalroot\{random folder}\{random folder}\config.ini - non-malicious
  • \?\globalroot\{random folder}\{random folder}\tdlcmd.dll - non-malicious
  • \?\globalroot\{random folder}\{random folder}\bckfg.tmp - non-malicious

It injects codes into the following process(es):

  • SPOOLSV.EXE

Other Details

This Trojan connects to the following website to send and receive information:

  • http://{BLOCKED}l01.com
  • http://{BLOCKED}10L.com
  • http://{BLOCKED}cv1.com
  • http://{BLOCKED}cv1.com
  • https://{BLOCKED}4cx00.cc
  • https://{BLOCKED}.{BLOCKED}.226.67
  • https://{BLOCKED}3.com
  • https://{BLOCKED}16b0.com
  • https://{BLOCKED}dden.in
  • https://{BLOCKED}fda88.com

It does the following:

  • Creates a copy of itself named %User Temp%\{temporary file name}.tmp
  • Changes its file characteristic to DLL
  • Patches a random .SYS file (detected as PE_TDSS.A) to enable it to automatically start upon system startup

(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.)

It deletes itself after execution.

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.426.03
FIRST VSAPI PATTERN DATE: 31 Aug 2010
VSAPI OPR PATTERN File: 7.427.00
VSAPI OPR PATTERN Date: 31 Aug 2010

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

AUTOMATIC REMOVAL INSTRUCTIONS

To automatically remove this malware from your system, use Trend Micro's special http://www.trendmicro.com/ftp/products/pattern/spyware/fixtool/SysClean-TROJ_TDSS.SMG.zip>fixtool. Download, extract, and run the said fixtool in the same folder where your latest Trend Micro pattern file is located. For more details, refer to the fixtool's incorporated text file.

MANUAL REMOVAL INSTRUCTIONS

Step 3

Remove malware files dropped/downloaded by TROJ_TDSS.FAT

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_TDSS.FAT. 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.

Related Malware