BleepingComputer.com: Dabber.A Worm - Buffer overflows Sasser

This worm manipulates a buffer overflow condition on Sasser's FTP service to propogate as yet another Internet worm. It's low risk unless someone is infected with Sasser.

Dabber.A Worm - Buffer overflows Sasser infections
http://secunia.com/virus_information/9394/dabber.worm.a/
http://vil.nai.com/vil/content/v_125300.htm
http://www.trendmicro.com/vinfo/virusencyc...e=WORM_DABBER.A
http://news.com.com/2100%2D7349_3%2D5212284.html

Dabber may be the first worm to attack systems using a flaw in a previous malicious program. In this case, the file transfer protocol (FTP) server installed by Sasser to enable the worm to transfer itself to new hosts has a buffer-overflow vulnerability. Dabber uses that security flaw to spread to the new machine. Once it copies itself to a new host, the worm will change the system settings so that operating system runs the malicious program every time it starts up. Dabber will also attempt to block other worms, which may have infected the machine, from running.