Trojan-Downloader.Win32.Agent.brit

Technical Details

I-worm.Brit is a simple worm that spreads via e-mail and by IRC channels.

This worm gets into a computer in the form of an e-mail message with the attached file "CHM", which contains the worm. The message has the following characteristics:

Message theme: "RE: Britney Pics"

Message text: Take a look at these pics ...
Regards,
%CurrentUser.Name%

Where %CurrentUser.Name% User Name.

Attached file name: BRITNEY.CHM

For the VBS-script to launch the worm needs ActiveX - therefore it tries to get users to turn ActiveX on by displaying the following message:

"Turn on ActiveX to see a photograph of Britney Spears".

While launching the worm finds the catalog containing the mIRC-client (a client that works with IRC system) and creates in it the file "SCRIPT.INI". In this file the worm scripts the mIRC client commands that send the worm to each computer included in the same channel as the infected computer.

After creating the file "SCRIPT.INI" the worm sends out a copy of itself to the first address in the MS Outlook address book and records a copy of itself in the Windows catalog.

Brit.g

Currently, Kaspersky Labs is familiar with five different versions of this program - b,c,d,e,f,g - , distinguished by their subjects and attachment file names.

The author of the most recent version, Brit.g, attempts to draw attention by exploiting today's most popular theme as bait - The World Cup football championship.

Brit.g:
Message Subject - RE: Korea Japan Results
Attachment File Name - KOREAJAPAN Results

However, due to a range of technical errors in the worm's code, the probability of it spreading "in the wild" is virtually zero.