According to data published by MessageLabs, spammers have turned away from file attachments and more toward spam embedded into hosted Web services, including Google Docs and Calendar as well as Microsoft SkyDrive.
"\[Spammers\] seem to have abandoned the attachments tactic that was so innovative in late 2007 and are now focused on exploiting free hosted applications which have become mainstream in 2008," said Mark Sunner, chief security analyst at MessageLabs. "The spammers are taking advantage of the fact that these services are free, provide ample bandwidth and are rarely blacklisted; this is one more addition to the growing list of ways the spammers have succeeded in outsmarting traditional detection devices."
MessageLabs said the overall amount of spam as a percentage of all email has increased, reaching 76.8 percent in May. The company also said that while the amount of new malware is down approximately 5 percent from April, roughly 30 percent all Web-based malware that it intercepted in May was new.