Jul 14, 2011 09:11 GMT  ·  By

The latest update introduced to the Malicious Software Removal Tool (MSRT) is designed to equip the free security solution in order to tackle malicious code designed to hijack web searches that users make and redirect them to sites hosting malware or displaying advertisements. Win32/Tracur and Win32/Dursg are the two malware families added to MSRT, which is designed to hunt down and kill a specific list of malicious code.

Impacting browsers including Internet Explorer, Firefox, Opera and Chrome, Tracur and Dursg are designed to infect Windows computers then monitor the users’ search activity.

Customers using machines compromised by Dursg or Tracur will start no longer getting to websites they’re searching for, but instead being redirected to various malformed Internet destinations.

“For instance, Win32/Tracur installs a browser helper object, or BHO, for IE to monitor web search queries. It also drops Win32/Dursg to install malicious extensions for Firefox and Opera,” revealed Rodel Finones, MMPC.

“User query results from search engines such as Google, Yahoo!, AOL, Ask and Bing will be redirected to a malicious site. To guarantee Win32/Tracur control, it modifies several registry entries.”

Dursg comes with similar functionality, but at the same time, this piece of malicious code is also being used by attackers as a vector to infect already compromised computers with even more malware.

“Win32/Dursg has been seen to be distributed with other malwares and file infectors such as Sality, Virut, Polip, Alureon, and Tracur, to name just a few, further assisting in its wide distribution,” Finones added.

Earlier this week Microsoft released four security bulletins as a part of its normal Patch Tuesday update release cycle.

As it is traditional, the software giant also provided customers with an updated version of the Malicious Software Removal Tool, starting to battle both Win32/Tracur and Win32/Dursg.

The Malicious Software Removal Tool (MSRT) is available for download here.