BleepingComputer.com: Storm Worm - Manipulates Invite Your Friends To Youtube Links

Spammers are exploiting YouTube's "invite your friends" function to send spam containing a variant of the "Storm worm." Bradley Anstis, director of product management at security firm Marshal, said that spammers are taking advantage of the YouTube function that lets people invite friends to view videos that they have viewed or posted. The function allows someone to e-mail any address from an account.

The YouTube help center also advises people to exclude the service @ youtube.com e-mail address from spam filtering lists--a fact, Anstis, said spammers are likely aware of.