Viruses/Worms News

Malware sites could target JScript flaws in Internet Explorer

Friday, September 11, 2009

Microsoft's September security update contains fixes for several vulnerabilities that security experts warn pose a threat to all versions of Windows using Internet Explorer (IE). Malware writers could exploit the IE flaws in drive-by download cyberattacks.

Of the five critical security vulnerabilities identified by Microsoft this week, four deal with security holes in IE’s JavaScript reader, which could allow maliciously crafted files on websites running JavaScript to infect a user's PC.

Andrew Storms, director of security operations at nCircle Network Security, said other security flaws got most of the initial attention, but the IE vulnerabilities have the most impact.

"Those are the big problem this month because they affect IE when the user is doing the normal thing on the computer - surfing the internet," Storms said, according to Computerworld.

Microsoft said the flaws exist in JScript 5.1 on Microsoft Windows 2000 Service Pack 4 and JScript 5.6, JScript 5.7 and JScript 5.8 on all supported releases of the Windows operating system - except Windows 7 and Windows Server 2008 R2.

If a user is logged on with administrative user rights, an attacker who successfully exploited this vulnerability could take complete control of an affected system, Microsoft said.