Although the MyDoom virus is mostly associated with e-mail attachments, it was first spread via the Kazaa file-sharing network. Now Sharman Networks say that built-in Bullguard software will protect Kazaa's users from MyDoom.
Users need updated versions of Kazaa to have Bullguard. Winamp5, icq2004-final, activation_crack, strip-girl-2.0bdcom_patches, rootkitXP, office_crack, or nuke2004 are names the virus takes when it attaches itself to users' Kazaa download folders.
Users need to make sure Bullguard is updated with the latest virus definitions. One problem is that many Kazaa users appear to have an older version of Kazaa or they ignore Bullguard. Thus, experts complain Kazaa is still a major virus route. Source