Virus writers have targeted MSN Messenger users with a childishly transparent, but at least partially effective, piece of social engineering.
The Henpeck (or Rodok) worm began circulating to MSN Messenger users earlier this week inviting users to download and feedback on the 'readme' file of a program.
The link contained in the message went to an executable file which, if users were daft enough to visit, attempted to download malicious files including a Trojan component, called Brat.
If the malicious payload is executed, the worm mails itself a instant message inviting all the contacts of an infected user to catch the pox too. Afterwards the worm displays a fake CD key generator.
Henpeck is also capable of stealing keys for the games Half-Life and Counter-Strike and sending them to a Hotmail email address.
The site containing the worm has now been pulled, but not before infecting a substantial number of people. Those users should get themselves disinfected since their machines have been compromised with the Brat Trojan and further mischief might follow otherwise.
It's not the first time virus writers have targeted Messenger users. Though most of these attacks haven't gone too far, they'll still given cause for concern.
In March, security clearing house CERT warned that IRC and instant messaging (IM) services are increasingly becoming vectors for social engineering attacks. Henpeck is a prime example of this phenomenon. ®