This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
This signature detects attempts by W32.Qakbot to download additional files onto the infected system.
W32.Qakbot is a worm that spreads through network shares and opens a back door on the compromised computer. It may also steal information and download more files on to the compromised computer.
Update your antivirus definitions and run a full scan.