Just received from my ISP:
The most recent virus threat to the Internet, W32.Welchia.Worm,
also known as, W32/Welchia.worm10240 [AhnLab], W32/Nachi.worm
[McAfee], WORM_MSBLAST.D [Trend], Lovsan.D [F-Secure],
W32/Nachi-A [Sophos], Win32.Nachi.A [CA], Worm.Win32.Welchia
[KAV], has been upgraded by Symantec to a Category 4 (of 5)
threat.
This worm attempts to download the DCOM RPC patch from Microsoft
Windows Update Web site, install it, and then reboot the
computer. It then checks for active machines to infect by sending
echo requests, or PING requests, which will result in increased
ICMP traffic.
The most recent virus threat to the Internet, W32.Welchia.Worm,
also known as, W32/Welchia.worm10240 [AhnLab], W32/Nachi.worm
[McAfee], WORM_MSBLAST.D [Trend], Lovsan.D [F-Secure],
W32/Nachi-A [Sophos], Win32.Nachi.A [CA], Worm.Win32.Welchia
[KAV], has been upgraded by Symantec to a Category 4 (of 5)
threat.
This worm attempts to download the DCOM RPC patch from Microsoft
Windows Update Web site, install it, and then reboot the
computer. It then checks for active machines to infect by sending
echo requests, or PING requests, which will result in increased
ICMP traffic.


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