
According to the Marshal TRACE team, the spammers are using YouTube’s own “Invite Your Friends” system to send large quantities of spam from genuine YouTube servers from service@youtube.com.
“YouTube users have a facility where they can invite their friends to view videos that they are looking at or have posted. This effectively allows them to email to any address from their YouTube account. This is the functionality that the spammers are exploiting,” said Bradley Anstis, Marshal’s director of product management.
Sophos researchers were questioning how successful the unsolicited messages would be at generating cash for the spammers, said Graham Cluley, senior technology consultant for Sophos.
"This is hardly the most compelling example of a spammer advertising his wares to an internet user," Cluley said. "It may be an effective way of waltzing past some spam defenses by hiding under YouTube's overcoat, but chances are that most people will simply erase the message in their inbox and not visit the site.”