Backdoor.Tidserv is a Trojan horse that uses an advanced rootkit to hide itself. It also displays advertisements, redirects user search results, and opens a back door on the compromised computer.

The threat Backdoor.Tidserv was discovered by Symantec Security Response Threat Severity Assessment on September 18, 2008 and was classified as Trojan.

Initial Daily Certified version of virus definitions for Norton security products was released on September 18, 2008 revision 008. It should be noted that users with the older versions of Norton Internet Security are limited to Daily LiveUpdate definitions. For more information, go to the page where the are described virus definitions available for Norton products.

Backdoor.Tidserv Threat Assessment

Component	Severity
Wild Level	Medium
Number of Infections	50 - 999
Number of Sites	3 - 9
Geographical Distribution	Medium
Threat Containment	Easy
Removal	Easy
Damage Level	High
Distribution Level	Low

According to the Symantec Threat Severity Assessment, overall risk of Backdoor.Tidserv is now categorized as «Low» — threat type characterized either as low or moderate wild threat (but reasonably harmless and containable) or non-wild threat characterized by an unusual damage or spread routine, or perhaps by some feature of the virus that makes headlines in the news. Read more about Threat Severity Assessment.

This threat affect the following operating systems:

• Windows XP
• Windows Vista
• Windows NT
• Windows Server 2003
• Windows 2000

More information about Backdoor.Tidserv, you can find on the official site of Symantec Corporation, where in addition to useful information you can find technical details and removal instructions: www.symantec.com

It is also recommended to read the article Network security threats, where you can find a brief description and explanation of the most dangerous security threats plus a few simple tips on how to protect your personal computer from them.