Sensors monitored by Symantec's DeepSight threat management service have reported a significant spike in traffic related to TCP port 2967, which Symantec has traced to scans generated by the "Sagevo" worm, recently released malware looking for systems running some of the company's enterprise antivirus software.
Flaws in both Symantec AntiVirus and Symantec Client Security were revealed in May and patched that same month. Sagevo, however, looks for unpatched machines, then tries to gain control of them.
Symantec reported that the number of sensors detecting scans of port 2097 were up over an uptick earlier in the week. "This is the most significant spike observed to date since the discovery of malicious code targeting the associated service," Symantec said in an alert to DeepSight subscribers.
"These scans are arriving in waves," says Vincent Weafer, senior director with Symantec's security response team. "When [the worm] is on an infected machine, it creates 512 threads on the box, and scans sequentially from the bottom up. [Meanwhile] any infected machines below that [IP address] also scan at the same time."