Malware type: Trojan

Aliases: Email-Worm.Win32.Zhelatin.x (Kaspersky), W32/Generic.aac!worm !! (McAfee), Bloodhound.W32.EP (Symantec), TR/Crypt.FSPM.Gen (Avira),

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 98, ME, NT, 2000, XP, Server 2003

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:


Distribution potential:



Barely three weeks into the new year, as the storm "Kyrill" ravaged over central Europe, another "storm" brewed. The new storm was a deluge of spam email messages that promised to bring information about Europe's most severe winter storm since 1999, with subject lines such as "230 dead as storm batters Europe", among others.

That is how this Trojan, arriving as attachment to the said email messages, came to be dubbed the "Storm" malware. But this Trojan is more than just a malware with a clever social engineering technique. Tagging WORM_NUWAR.CQ along, it created a partnership that staged a complex attack.

To read a comprehensive article about the routines and ultimate goals of the TROJ_SMALL.EDW-WORM_NUWAR.CQ tandem, click here: Storms into Inboxes, Teams Up with NUWAR to Create Unique Network.

This Trojan may be downloaded and executed by other malware such as TROJ_SMALL.EDW. It gathers email addresses from the affected computer and sends them to an unknown recipient via the IP address 81.177.{BLOCKED}.27/1.jpg.

For additional information about this threat, see:

Description created: Jan. 22, 2007 11:37:43 PM GMT -0800


File type: PE

Memory resident:  No

Size of malware: 6,275 Bytes

Initial samples received on: Jan 21, 2007

Compression type: UPX


Payload 1: Gathers email addresses


This Trojan may be downloaded and executed by other malware such as TROJ_SMALL.EDW. It searches for files with the following file extensions in the affected system:

  • .adb
  • .asp
  • .cfg
  • .cgi
  • .dat
  • .dbx
  • .dhtm
  • .eml
  • .htm
  • .jsp
  • .lst
  • .mbx
  • .mdx
  • .mht
  • .mmf
  • .msg
  • .nch
  • .ods
  • .oft
  • .php
  • .pl
  • .sht
  • .shtm
  • .stm
  • .tbb
  • .txt
  • .uin
  • .wab
  • .wsh
  • .xls
  • .xml

Once found, it opens these files then searches their file bodies for email addresses. It ignores email addresses with the following substrings:

  • @avp.
  • @foo
  • @iana
  • @messagelab
  • @microsoft
  • abuse
  • admin
  • anyone@
  • bsd
  • bugs@
  • cafee
  • certific
  • contract@
  • feste
  • free-av
  • f-secur
  • gold-certs@
  • google
  • help@
  • icrosoft
  • info@
  • kasp
  • linux
  • listserv
  • local
  • nobody@
  • noone@
  • noreply
  • ntivi
  • panda
  • pgp
  • postmaster@
  • rating@
  • root@
  • samples
  • sopho
  • spam
  • support
  • unix
  • winrar
  • winzip

The harvested email addresses are sent to an unknown recipient via the IP address 81.177.{BLOCKED}.27/1.jpg.

This Trojan runs on Windows 98, ME, NT, 2000, XP, and Server 2003.

Analysis By: Mark Anthony Balanza

Revision History:

First pattern file version: 4.202.01
First pattern file release date: Jan 21, 2007


Minimum scan engine version needed: 8.000

Pattern file needed: 4.267.00

Pattern release date: Feb 13, 2007

Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.


Note: To fully remove all associated malware, perform the clean solution for TROJ_SMALL.EDW.

Important Windows ME/XP Cleaning Instructions

Users running Windows ME and XP must disable System Restore to allow full scanning of infected computers.

Users running other Windows versions can proceed with the succeeding solution set(s).

Running Trend Micro Antivirus

If you are currently running in safe mode, please restart your computer normally before performing the following solution.

Scan your computer with Trend Micro antivirus and delete files detected as TROJ_AGENT.JVK. To do this, Trend Micro customers must download the latest virus pattern file and scan their computer. Other Internet users can use HouseCall, the Trend Micro online virus scanner.

Trend Micro offers best-of-breed antivirus and content-security solutions for your corporate network, small and medium business, mobile device or home PC.