Friday, March 16, 2007

Spam Evolution

By Rob Dee

Symantec has just produced a report on spam messages, what they promote and how they attempt to bypass filters designed to stop spam. The report doesn't really contain any major surprises to me, although it does confirm what I have been seeing in my own studies.

The overall amount of spam made up 70% of all email messages, which is lower than several other sources estimate, but it must be remembered that Symantec takes samples from their own sources and spam may have already been filtered (at the network level) prior to entering this sample data.

The big talking point of the report is that Pornographic spam now makes up only 3% of all spam monitored by Symantec. This is the lowest percentage makeup ever recorded. Clearly - pornography isn't selling for spammers the same as other products. Perhaps everyone who needs enlarging has got it?

The increase in the amount of spam that uses images continues. As bayesian filters catch more and more text based spam, the spammers have changed their method of attack to sending pictures of words. This allows them to use randomised text to beat the Bayesian filters, but once opened the text is overlapped with an image sending the spammers true message. This is not a new tactic, but it has evolved slightly with the increasingly predominant practice of slanting or distorting the writing on these pictures. This is aimed at defeating OCR(Text recognition) software.

The final trend of note in the Symantec report is that non-english speakers are being targeted more than in the past, particularly by casino based spam. French, German and Italian language casino spam has sen a dramatic rise, and picture based spam targets all languages.

On a personal note I have seen an increase in this localisation of spam. I have received no inappropriate language based spam, but I have noted that the distribution of spam to me .com vs my .co.nz email addresses has shifted. I suspect that spammers are hitting localised email addresses with localised content, which is undoubtedly where the increase in language specific spam originates.

With an estimated 70-90 billion spam messages sent every day, the problem is not going away. Don't wait for someone to solve the problem for you, visit STOPSPAMNOW.info and download your free ebook on how to win the fight against spam.

Article Source: http://EzineArticles.com/?expert=Rob_Dee

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