The worm spreads in a email with the following characteristics:
RE: Britney Pics
Body: Take a look at these pics ...
(the name of the infected user)
The attachment name is variable and can be something else than "Britney.chm" as well.
If the user executes the attached file, the following screen is displayed:
However, in a default installation of Windows, the following warning dialog is also displayed:
After this the actual script in the compiled HTML help file will be executed if the user selects "Yes" the dialog.
At this point, the worm will go through C:, D: and E: drives in the system and replace the "script.ini" file from mIRC installation directory if such is found. After that worm is sent thru mIRC with a filename "Britney.chm" previosly saved into Windows installation directory.
The worm sets a registry key that is used as an infection marker, so the worm will not spread more than once from an infected system.
The registry key is:
Finally the worm sends an infected message only to the first recipient in the first address book. All this means that the worm is sent only once from an infected system.
Variant:Chick.F (I-Worm.Brit.g, Brit.G, VBS/Chick.F@m)
Chick.F also known as Brit.G is variant of Chick worm which disguises itself as World Cup 2002 results.
F-Secure Anti Virus detects this worm with the updates published on June 7th, 2002.
More information on Chick.F (Brit.G) you can find here: