Microsoft issued a security patch yesterday that fixes six holes in its Internet Explorer web browser, just as a nasty internet worm that threatens to overwrite certain PC files continued its assault on users.
The 'cumulative' patch, made available for download yesterday, fixes holes in versions 5.01, 5.5 and 6.0 of IE.
It addresses six vulnerabilities discovered in the past few months, one of which could allow a malicious hacker to run code on another user's computer, Microsoft said.
The software company gave the vulnerabilities a 'critical' rating and advised users to download the patch from its website immediately.
One of the holes could disguise the name of a file posted on a website so a user might be tricked into opening or saving the file without knowing it is unsafe. Other vulnerabilities could allow an attacker to run code or view certain files on a user's PC, or run a script even when the user has disabled scripting, Microsoft said.
In addition, the cumulative patch includes a handful of previously released fixes for other holes found in the browser. One of those fixes is designed to block a worm known as 'Klez', which has threatened some IE users since it first circulated via email in October 2001.
The same vulnerability in Internet Explorer that allows for Klez to do its harm was partly responsible for the Nimda virus that emerged last year, Weafer said. "We've had other worms in the past that exploited the same vulnerability," he said.