Mail-Filters.com, Inc. has detected a rise in new spam techniques within the past three (3) days, including the use of audio files. Spammers are sending email messages that contain an attached MP3 audio file that usually has a name like, 'llcoolj.mp3' indicating it is a song or an artist. When you click on the file it plays a message that this is an 'Investor Alert', and then promotes a company and stock symbol -- a classic 'pump and dump' scam. The use of audio demonstrates yet another method that spammers have deployed over the past 12 months, including the use of Microsoft Excel files, PDF files, and other image files, to deliver their message while avoiding many spam filters.
In reference to the technique of using MP3 audio files, Ben Westbrook, CTO of Mail-Filters, stated, "While the current distribution of spam that is attaching MP3 files accounts for less than 3% of the total spam distribution, this new technique signals yet another volley by spammers to get their message through. This attack is significant, not only because of the new technique, but because the size of the MP3 file is 10 times larger than your average spam message, it can clog email servers and a company's bandwidth very quickly. The Mail-Filters technology combats this new technique in two different ways: through identification of the bot networks sending the spam messages, and by creating Bullet Signatures to catch the messages outright. While many competitive anti-spam products failed to catch the new threat, the Mail-Filters technology withstood the attack without any additional effort."