smss.exe - Windows Session Manager
The smss.exe process represents the running portion of the Windows Session Manager Subsystem. It's responsible for managing sessions on your system. It's responsible for launching the Winlogon and Win32 (csrss.exe) processes, as well as for setting system variables. After it has launched these processes, smss.exe waits for Winlogon or csrss.exe to end. If one of these processes is terminated normally, the system shuts down. If either process ends unexpectedly, smss.exe causes the system to stop responding (hang).This process is a critical component of the Windows operating system, and should not be altered or tweaked in any way. It's found on many Windows versions, including Windows 2000, XP, and Vista. Server editions also use the smss.exe process.
The legitimate copy of this file is always found in C:\windows\system32. The system will run its smss.exe process under the SYSTEM user ID, which can be verified using Task Manager. If other copies of this file are found on your PC, or you find copies running under a different user ID, it probably represents a malware application that's attempting to hijack a legitimate Windows file name and process in order to escape detection.
Known malware applications that attempt to hijack the smss.exe name include: W32.Dalbug.Worm, Adware.DreamAd, W32.Resdoc, Adware.Advision, Backdoor.IRC.Flood.F, and Backdoor.IRC.Aladinz.O. Apparently this file is a popular one with virus authors, since many other variants have used the same name. Symantec and other antivirus scanners have identified all the above variants. Users who maintain up to date copies of their virus definition files should be able to remove these known viruses successfully.
As always, if you suspect a malware infestation you should download and run a current copy of an antivirus/malware scanner in order to isolate and remove the offending application. Be sure to obtain the most recent definition files, since these are critical to the removal of current malware variants.
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