Metamorphic virus

Virus that changes its own code with each infection

A metamorphic virus is one that is capable of rewriting its own code with each infection, or generation of infections, while maintaining the same functionality.

The rewriting process allows each infection to appear different from others, but the changes are not supposed to affect the functionality of the code. This is intended to avoid detection by anti-malware software, but can usually be overcome via emulation or other techniques, and in many cases is deployed in a flawed manner leading to large numbers of misinfections. The complex technology required to do the rewriting is known as a metamorphic engine, and the same such engine may be implemented in several different virus variants.

The term is often used interchangeably with polymorphic virus.

Quick Links



Poll

When do you install software updates?
As soon as they are released
As soon as I have some time
I take my time, but I always install them eventually
Only when I feel it is absolutely necessary
Never
Leave a comment
View 12 comments

Jobs Recruit Sidebar

Twitter Feed

virusbtn: RT @emailsecmatters: The typical spam message has sources as diverse as the spam lunch meat: http://ht.ly/2yucd
2 hours ago


virusbtn: Can anyone write a rap about our RAP tests (http://bit.ly/255ySQ) and submit it to the Symantec competition http://bit.ly/bOJg8r
5 hours ago


VB2010

VB2010 VB2010 will take place 29 September - 1 October 2009 at the Westin Bayshore, Vancouver, BC, Canada.
Virus Bulletin currently has 208,224 registered users.