MS08-038 is not categorized as virus, worm, Trojan or backdoor. It is an important vulnerability in Windows Explorer on Windows 2008/Vista computers, which allows arbitrary code to be remotely executed in the vulnerable computer.
If exploited successfully, MS08-038 allows hackers to gain remote control of the affected computer with the same privileges as the logged on user. If this user had administrator rights, the hacker could take complete control of the system: create, modify or delete files, install programs, create new user accounts, etc.
This vulnerability can be exploited by sending a specially crafted saved-searched file to a vulnerable computer and enticing users to open it. This file can be distributed using several methods, such as email, instant messaging programs, web hosting etc.
If you have Windows 2008/Vista installed on your computer, it is recommended to download and apply the security patch for this vulnerability. Access the web page for downloading the patch.