Spammers turn back the clock with ASCII art, Sophos reports

March 15, 2005 Sophos Press Release

Experts at SophosLabs™, Sophos's global network of virus and spam analysis centres, have identified that some spammers are using a technique from the early days of computing in an attempt to slip their unwanted messages past anti-spam software.

In the early days of computing, when monitors could commonly only display text rather than graphics, computer users would create pictures by carefully placing characters. Most examples of ASCII art required a fixed width font (like that found on a traditional typewriter) for presentation.

Devotees of ASCII art continue to share examples of their art work on the internet, but it is rarely used in regular email communication because of the ability to use graphical images.

Sophos researchers have identitifed that some spammers are now using ASCII art in an attempt to reach audiences for their products. One of the latest examples seen by Sophos is a spam message advertising various forms of medication:

A spam message using ASCII art in an attempt to sell medication online.
A spam message using ASCII art in an attempt to sell medication online.

"By using old-fashioned ASCII art with carefully positioned randomly chosen letters spammers are attempting to sneak past email filters hunting for phrases commonly used in spam," said Graham Cluley, senior technology consultant for Sophos. "It's a crafty trick - the spam email is advertising drugs like "Viagra" and "Cialis" without having to use the actual words. But sophisticated anti-spam software can still help businesses prevent this kind of nuisance message entering their company."

Sophos recommends companies protect themselves with a consolidated solution which can defend businesses from the threats of both spam and viruses.