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Yaha usurps Klez
Monthly malware chart
Yaha-E displaced Klez as the most common viral menace on the Internet over the last month, according to Messagelabs.
The managed services firm has blocked Yaha-E 367,158 times so far in July, relegating Klez-H (332,343 interceptions) to second place in its monthly viral charts. Sobig-E (blocked 188,235 times) and BugBear-B (108,206) and Sobig-A (63,076) make up the remaining stop five places in MessageLabs chart, released last night.
The company reports that one in 166 emails processed this month contained a virus, about average for this time of year.
None of the viruses that make up MessageLabs top ten chart are new. While fewer in number, backdoor-trojans are increasing appearing on MessageLabs' anti-malware radar screens.
"In recent months, an emerging trend has also been observed in the distribution of backdoor-trojans via email, typically sent as an attachment to spam emails in very large volumes. Typically these trojans are being altered and redeployed, almost on a daily basis so as to sneak past anti-virus software," MessageLabs reports.
For example, in July MessageLabs intercepted the following patterns of variants for the same trojan, in almost as many days: Downloader.DI!Eloan (1,083 interceptions), Downnloader.DI!WFd7f3 (589), Downloader.DI!Heloc (522) and Downloader.DI!WF97bc (110).
The company also operates an anti-spam service. In July, 79.7 million of the 156.6 million emails - just over 50 per cent - scanned by MessageLabs' Anti-Spam service turned out to be junk mail. ®
Top ten viruses blocked by MessageLabs in July
Trojan turns victims into DDoS, spam zombies
Trojan serves porn off home PCs, not many dead
Virus writers boost output in 2003
VX writers release sequel to infamous Sobig worm
Unhappy new Yaha
Klez-H enjoying its final days on infamy?