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.
"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.