Synonyms and Poor Spelling: The Spammer's Secret Weapons

Spammers are increasingly using two simple but effective methods of obfuscating their messages just enough to fool anti-spam email filtering systems.

The human brain is capable of reading just about any butchering of a word as being the one originally intended. In fact, if you get the first and last letters correct, you can pretty much order the remaining ones in any way and it will be perceived as intelligible text.

Spam filter software is unfortunately not quite this smart. While such efforts look painfully unprofessional, they do get the message through to the user.

Another trick is to run the message through an automated thesaurus script which replaces a certain percentage of words with synonyms. Again, the result commonly doesn't look pretty. It does work though.

These techniques in combination with using hijacked computers to send spam make for some tough to filter messages. Fortunately, messages of these types make up only a few percent of all junk email. Most marketers seem to retain some pride at the expense of being picked up by the spam filters. These messages however make up a very large percentage of all email that makes it past efforts to eliminate spam.

In the long run, Spammers tend to follow the road that leads to improved deliverability at all costs. As spam becomes uglier, anti spam mail systems will need to develop new strategies to recognize such messages.

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