Developers from Mozilla foundation have issued the latest patch for everyone’s favorite Web-browser, bringing it to version 2.0.0.6.

Included in the update are some security fixes that address vulnerabilities found in both FireFox and Internet Explorer 7. Users could face a "highly critical" risk if they have both IE and Firefox version 2.0, or later, loaded on their computer. The trouble begins when browsing a malicious site while using IE and it registers a "firefoxurl://" URI (uniform resource identifier) handler, which allows the browser to interact with specific resources on the Web. As a result, users may find their systems remotely compromised.

Oliver Friedrichs, director of Symantec's Security Response Center, said about the double IE7/FF2.0 vulnerability that "You have two very complex applications that are not playing well together and leading to a security issue. The components themselves are secure as stand-alone products but not together."

The update that fixes the security hole is considered critical, and is said to have also affected Mozilla’s Thunderbird mail client.

The second patch is considered less critical and fixes a “privilege escalation through chrome-loaded about:blank windows”.

New research indicates that FireFox advanced more than 20% in Europe concerning market share compared to January 2007, some European countries showing double digit adoption rates for the XUL-based, open source browser.

According to French web metrics firm XiTiMonitor, FireFox’s overall market share in the 32 European countries it measures has grown to 27.8 percent, up from just over 20 percent in January 2006.