Effects 

MS09-022 is not categorized as virus, worm, Trojan or backdoor. It is a group of critical vulnerabilities in the Windows Print Spooler on Windows 2008/Vista/2003/XP/2000 computers, which allows arbitrary code to be remotely executed, local privilege escalation and information disclosure in the vulnerable computer.

The Print Spooler Service manages the printing process. However, there is a vulnerability in this service.

The addressed vulnerabilities are:

• Buffer Overflow in Print Spooler vulnerability: this remote code execution vulnerability is due to the improper parsing of certain printing data structures.
  
  If exploited successfully, MS09-022 allows hackers to gain remote control of the affected computer with the same privileges as the logged-on user.
• Print Spooler Read File vulnerability: this information disclosure vulnerability occurs because the Windows Printing Service does not properly check the files that can be included with separator pages.
  
  If exploited successfully, an attacking user could read or print any file on an affected system. 
• Print Spooler Load Library vulnerability: this elevation of privilege vulnerability occurs because the Windows Print Spooler does not properly validate the paths from which a DLL may be loaded.
  
  If exploited successfully, MS09-022 allows to gain unauthorized privileges on a computer or network.

If you have a Windows 2008/Vista/2003/XP/2000 computer, it is recommended to download and apply the security patch for this vulnerability. Click here to access the web page for downloading the patch.