McAfee inadvertently speeds creation of Metaploit IE exploit pack

A security researcher has credited McAfee for helping him to develop exploit code that cracks open an unpatched flaw in older versions of Internet Explorer.

Moshe Ben Abu (AKA Trancer00t) used the flaw in IE 6 and 7 in knocking-up a module for the open-source Metasploit exploit database.

"I didn't find the vuln', just found it in the wild. With a little help from McAfee (http://j.mp/c4W3xA) :-)," the Israeli security researcher noted in a Twitter update on Thursday.

Microsoft acknowledged that the flaw, which stems from an invalid pointer reference, affects IE 6 and 7 and creates a possible mechanism for hackers to drop malware onto vulnerable systems. IE8, the latest version of Microsoft's web surfing software, isn't vulnerable.

Redmond's advisory, published on Tuesday, which provides workarounds for users unable to upgrade to IE 8, makes it clear that the vulnerability is already being used in targeted attacks.

These attacks are geared towards dropping backdoor Trojans, detected by McAfee and other security firms, onto vulnerable systems.

The flaw is separate from an earlier, unpatched IE flaw that involves tricking users users into pressing the F1 button, which is normally used to present a help screen, as explained in our earlier story here.

Trancer00t created code that allowed sysadmins and other interested parties to test networks for the presence of a flaw already under attack by miscreants.

McAfee's blog post helped Ben Abu to locate an exploit already developed and published by the bad guys, something he'd have been able to locate anyway. Nonetheless the incident has prompted McAfee to more closely review blog posts for stray clues, CNET reports

"We regularly sanitize blog content to prevent providing information that might assist attackers, while at the same time providing a service to customers and the security community to help improve protection levels," a McAfee spokesman said.

"The post in question did not contain enough information to directly lead anyone to exploit code. However, we regret that in this unique situation the post did contain details that may have given exploit writers a starting point to hunt for exploit code. Future blog posts will be subject to additional sanitization." ®