Sophos Identifies the Most Prevalent Spam Categories of 2005

While emails peddling snake-oil meds and low-interest loans continue to irk computer users and clog corporate networks, dangerous new categories of spam are becoming more prevalent according to Sophos, which today published the results of its research on the most prominent spam categories during the first six months of the year.

Researchers from SophosLabs analyzed the spam received in its global network of spam traps. Sophos experts found that "pump-and-dump" stock scams are on the rise, and unsolicited pill or medication email, including generic or non-brand name versions of Viagra and other pharmaceuticals, accounted for more than 40% of all spam traffic.

The top five spam categories spanning January 2005 through June 2005 are as follows:

1. Medication/pills 41.4%
2. Mortgage 11.1%
3. Pornography 9.5%
4. Stock scams 8.5%
5. Product 8.3%
Other 21.2%

Sophos's analysis shows that, during the first half of 2005, the volume of stock scam spam has increased at an average rate of 10% per month.

Pump-and-dump campaigns tend to run for short durations, keeping overall volume low. Even though some of the information provided is accurate, the deceptive and unsolicited nature of the messages qualifies them as spam. The majority of stock scam spam campaigns employ obfuscation techniques, using word variations such as "st0ck" or "stox" to avoid being caught by spam filters. Messages can arrive in many different formats, such as HTML or plain text, and are almost always sent via hijacked PCs known as zombies.

Sophos recommends that the most effective way for businesses to reduce spam and other threats is to adopt a multi-layered defense as well as implement a best practice policy regarding email account usage. Users can also learn how to best minimize the influx of unwanted email by following a few simple guidelines.