Analysis by: kathleenno
ALIASES:

Trojan.Gen (Symantec); Trojan:Win32/Alureon.ET (Microsoft); Trojan-Downloader.Win32.Agent.fxzk (Kaspersky); Mal/Emogen-Y (Sophos)

 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 may arrive as a file dropped by TROJ_TDSS.WIN.

Its primary function is to log the Internet browsing activities of the user by keeping a record of keywords entered in search engines. It monitors specific strings in the browser address bar for this purpose.

It checks processes with certain strings in order to monitor browser-related activities.

This Trojan may be dropped by other malware.

  TECHNICAL DETAILS

File Size: 24,580 bytes
File Type: DLL
Memory Resident: Yes
Initial Samples Received Date: 11 Mar 2011

Arrival Details

This Trojan may be dropped by the following malware:

  • TROJ_TDSS.WIN

Installation

This Trojan adds the following mutexes to ensure that only one of its copies runs at any one time:

  • Global\{random GUID}

It is injected into the following processes running in memory:

  • svchost.exe

NOTES:
It checks processes with the following strings in order to monitor browser-related activities:

  • explo
  • firefox
  • chrome
  • opera
  • safari
  • netsc
  • avant
  • browser
  • mozill
  • wuauclt
Its primary function is to log the Internet browsing activities of the user by keeping a record of keywords entered in search engines. It monitors the following strings in the browser address bar for this purpose:
  • www.google.
  • /search
  • /gen_204
  • /custom
  • as_epq
  • as_q
  • as_oq
  • bing.
  • search.yahoo.com
  • .altavista.com
  • /web/results
  • .ask.com
  • /web
  • www.exalead.com
  • /search/web/results
  • www.alltheweb.com
  • search.lycos.
  • tab=web
  • query
  • gigablast.com
  • cuil.com
  • .aol.
  • /aol/search
  • query
  • entir web.com
  • md=web
  • www.search.com
  • www.mamma.com
  • /result
  • mytalkingbuddy.com
  • searchservice.myspace.com
  • type=web
  • qry
  • search.conduit.com
  • /results
  • search.toolbars.alexa.com
  • alltheinternet.com
  • /ws/results/web/

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.894.03
FIRST VSAPI PATTERN DATE: 11 Mar 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

Remove malware files dropped/downloaded by TROJ_TDSS.WIM

    TROJ_TDSS.WIN

Step 3

Scan your computer with your Trend Micro product and note files detected as TROJ_TDSS.WIM

Step 4

Restart in Safe Mode

[ Learn More ]

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_TDSS.WIM. 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.


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