03/02/2012

The DNSChanger Trojan malware is running on computers at half of the Fortune 500 companies and on 50 percent of all federal government agencies' PCs in the US, according to a new report.

Computer security firm Internet Identity (IID) said that despite the FBI moving on the virus in November to stop it redirecting users to malicious sites, infected systems are now facing a "second vulnerability".

The concern now is that DNSChanger is able to disable anti-virus and regular software updates - exposing computers to other incoming threats.

IID is now offering to scan enterprises' machines for infections for free.

The company said: "IID can identify malware infestations … with its ActiveKnowledge Signals service, which externally detects and diagnoses malicious … activities occurring on an enterprise's network via the indicators these activities give off when communicating on the internet."

Users infected with the DNSChanger virus are also facing the prospect of an internet blackout on March 8th, when legitimate servers used in place of the Trojan's servers are set to be taken offline.