Threat Management Report.

Sophos revealed the top ten malware threats of 2005, in a new in-depth report into the years most pressing security issues. In a year that has seen the number of new threats rise by 48%, the lingering Zaft-D worm has taken the number one spot in the virus chart while last year's hardest hitting virus, Netsky-P, has dropped to second place. In contrast, Sober-Z--only unleashed in November 2005--has already climbed to third position as it continues to disrupt and clog networks worldwide.

The Sophos Security Threat Management Report 2005-which can be downloaded from http://www.sophos.com/securityreport2005--reveals that on average, one in every 44 emails was viral during 2005. This rose to one in twelve during major outbreaks, while 15,907 new malware threats were identified-The top ten viruses of the year are as follows:</p> <pre> Pos Name

Percentage First seen I-Zafi-D 16.7% December 2004 2. Netsky-P 15.7% March 2004 3. Sober-Z 6.0% November 2005 4. Sober-N 4.3% May 2005 5. Zafi-B 4.0% June 2004 6. Mytob-BE 3.9% June 2005 7. Mytob-AS 3.8%

June 2005 8. Netsky-D 3.0% March 2004 9. Mytob-014

1.9% October 2005 10. Mytob-EP 1.8% June 2005 Others

38.9% </pre> <p>Comment

Interestingly, while all of the top ten threats are Windows-based worms, the number of Trojan horses written during 2005 outweighs worms by almost 2: 1. In addition, the percentage of malware that includes spyware components rose from 54.2% in January to 66.40% by the end of the year' These figures confirm the notion that malware authors are engaging in targeted attacks, rather than widespread bombardment, and also help explain a rise in the amount of spam spewed out by zombie computers--now accounting for over 60% of the worlds spam.

Unlike viruses or worms, Trojans cannot replicate on their own, meaning that they must be deliberately emailed or planted on websites in order to spread.

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