If you're lucky enough to be running Linux or have a Linux router, run this script:

#!/bin/sh

for LUSER in `grep "winnt" /var/log/httpd/error_log | awk '{print $8}' | sed -e s/]//`; do
if [ ! "`ipchains -L -n | grep $LUSER`" ]
then ipchains -A input -s $LUSER -d 0/0 -j DENY
fi
done

This script will block all of the guys that are infected and keep your bandwidth from being hogged.

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