Explorer Flaws Reach Critical Level

by CXOtoday Staff    Jan 10, 2005

Critical flaws uncovered in Internet Explorer 6 could enable hackers to run script code on a user’s system via a specially crafted Web page. The exploit code could be used to infiltrate computers running Windows XP, even if Service Pack 2 patch has been used.

According to Secunia, the vulnerabilities can be exploited by malicious people to compromise a user’s system, conduct cross-site/zone scripting bypassing a security feature in Microsoft Windows XP SP2.

The new exploit is fully automated, requiring the user only to visit a Web page in Explorer. Other browsers and operating systems are not affected.

Researchers have identified three separate, but related issues in IE: a bug in the validation of certain drag-and-drop events, and zone restriction errors with embedded HTML Help ActiveX controls.

While the first flaw can be avoided by disabling the “drag and drop or copy and paste files” option, the new exploit does not rely on this particular bug.

The HTML Help control flaw bypasses the “Local Machine” Zone lockdown, one of SP2’s key features, that makes it difficult for attackers to execute script on a local system.