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28 Jul 2004

Microsoft targeted by MyDoom-piggybacking Zindos worm, Sophos reports

Microsoft's website is targeted by the Zindos worm
Microsoft's website is targeted by the Zindos worm

The Zindos worm infects computers already compromised by MyDoom-O, and launches an attack against Microsoft's website

Experts at Sophos believe that the author of the prevalent W32/MyDoom-O email worm has released another worm called Zindos, designed to infect those hit by MyDoom-O and launch a denial of service attack against Microsoft.

The W32/Zindos-A worm spreads via the backdoor opened by the W32/MyDoom-O worm released earlier this week, which managed to disrupt access to Google and other internet search engines.

"Three minutes after a PC is infected by the Zindos worm, it will begin to launch a denial of service attack against Microsoft's main website -," said Graham Cluley, senior technology consultant for Sophos. "All computer users have a responsibility to ensure their PCs are secured with up-to-date anti-virus and firewall protection to ensure they are not unknowingly collaborating with the virus writer's illegal activity."

It is not the first time the author of MyDoom has targeted the Microsoft website. In January and February of this year the MyDoom-B and MyDoom-F worm variants launched separate attacks against Microsoft has issued a $250,000 reward for information leading to the conviction of MyDoom's author.

"For whatever reason, the person behind the MyDoom worm really doesn't like Microsoft," continued Cluley.

Sophos continues to recommend computer users practise safe computing as well as running up-to-date anti-virus software.

About Sophos

More than 100 million users in 150 countries rely on Sophos as the best protection against complex threats and data loss. Sophos is committed to providing complete security solutions that are simple to deploy, manage, and use and that deliver the industry's lowest total cost of ownership. Sophos offers award-winning encryption, endpoint security, web, email, mobile and network security solutions backed by SophosLabs - a global network of threat intelligence centers.

Sophos is headquartered in Boston, US and Oxford, UK. More information is available at