Email-Worm:W32/Zhelatin.CQ

The Zhelatin.CQ worm started to spread very late on April 8th, 2007. The worm spreads in emails with war-related subjects as an attachment named "video.exe", "movie.exe", "click me.exe" and so on. The worm creates its own peer-to-peer network.

After the worm's file is started by a user, it drops a randomly named file into the same folder where it was started from and runs it. This file installs a rootkit and p2p (peer-to-peer) component into the Windows System folder. The file name is wincom32.sys.

Rootkit

The installed component has rootkit features: it hides its Registry keys and active process so that an anti-rootkit engine is needed to reveal them.

In addition, this component drops a text file named wincom32.ini into the Windows System folder. This file contains a list of clients for the worm's peer-to-peer network. The peer names and access ports are encoded. Here's an example of the file's contents:

• [counter] Counter=0 [peers] 003964D3640550573F800125725481EF=5326859A123900 004982069E5DB75721B54CFF33A26170=5955FC93123900 00A1836AE91D076BC265F9735204714F=451AAE831EBF00

The dropped file also has a blacklist area, but it's empty at the moment.

Propagation

The worm decodes the clients' addresses and access ports and connects itself to the peer-to-peer network. A significant number of UDP connections can be observed when the worm is trying to connect to its p2p network.

While taking the above actions, the copy of the worm that remains in memory starts its spreading cycle. It creates a mutex named klllekkdkkd and scans files on local hard disk drives for victims' email addresses.

The worm ignores email addresses if they contain any of the following substrings:

• .gov
• .mil
• microsoft

Then the worm starts to spread in emails. It sends messages with the following subjects to all harvested email addresses:

• Iran Just Have Started World War III
• Israel Just Have Started World War III
• Missle Strike: The USA kills more then 1000 Iranian citizens
• Missle Strike: The USA kills more then 10000 Iranian citizens
• Missle Strike: The USA kills more then 20000 Iranian citizens
• USA Declares War on Iran
• USA Just Have Started World War III
• USA Missle Strike: Iran War just have started

The subjects are war-related and alarming, a common social-engineering trick to draw recipients into executing the attachment. The worm always attaches itself to the emails that it sends out. The attachment names can be any of the following:

• Click Here.exe
• Click Me.exe
• More.exe
• Movie.exe
• News.exe
• Read Me.exe
• Read More.exe
• Video.exe

When a recipient of such email opens the attachment, his/her computer becomes infected and the worm continues its spreading cycle.

Payload

The worm kills processes if they have the following substrings in their names:

• anti
• avg
• avp
• blackice
• firewall
• f-pro
• hijack
• lockdown
• mcafee
• msconfig
• nav
• nod32
• rav
• reged
• spybot
• taskmgr
• troja
• viru
• vsmon
• zonea

Registry Modifications

Creates these keys:

• [HKLM\System\ControlSet001\Services\wincom32] @ = "%WinSysDir%\wincom32.sys"