At least four in five e-mail messages transmitted are actually spam, according to Cupertino, Calif.-based Symantec Corp.
The security software vendor has published the April issue of its State of Spam report.
In March, many spammers took advantage of mail transfer agents to use backscatter, whereby messages are sent with forged from addresses to a large list of addressees, many of which are invalid, in the hopes that some will land in users’ inboxes after they are bounced back from invalid addresses.
One spammer group is telling recipients they have won, $2 million in a lottery held to promote the 2010 South African World Cup, in the hopes they will provide the personal financial information required to collect the winnings.
Although some peddlers of impotence treatment drugs are attaching Zip files to their spam messages, Symantec says these only accounted for 0.5 per cent of spam attacks in March.