MS08-040 is not categorized as virus, worm, Trojan or backdoor. It is a group of important vulnerabilities in certain versions of SQL Server, which allows local privilege escalation in the vulnerable computer. The affected components are: SQL Server 7.0, SQL Server 2000, SQL Server 2005, Data Engine (MSDE) 1.0, SQL Server 2000 Desktop Engine (MSDE 2000), SQL Server 2000 Desktop Engine (WMSDE) on Windows 2003/2000 and Windows Internal DataBase (WYukon) on Windows 2008/2003.
If exploited successfully, MS08-040 allows to gain unauthorized privileges within the system. This would allow hackers to gain the same user rights as the logged-on user, allowing them to take complete control of the system and carry out actions such as installing programs, viewing, changing or deleting data, creating new accounts with administrative rights, etc.
If you have any of the vulnerable versions mentioned above, it is recommended to download and apply the security patch for this vulnerability. Access the web page for downloading the patch.