Microsoft rushes to fix security flaw in Explorer browser

Microsoft Corp is rushing to fix a security flaw in its Internet Explorer browser that is already being used in "limited, targeted attacks," as anti-virus firms and the US government advise switching to alternate products.

To take over a user's personal computer through the browser's vulnerability, a hacker would have to persuade that person to click on a link to view a malicious website, Microsoft said in an advisory.

Some edition of Internet Explorer runs on 58 per cent of all desktop PCs, according NetMarketShare, compared with 18 per cent for Google Inc's Chrome, the No. 2 browser.

"An attacker who successfully exploited this vulnerability could gain the same user rights as the current user," Microsoft said in the advisory, issued on April 26.

The flaw exists in Internet Explorer versions 6 through 11, which means it will affect users of Windows XP, the operating system that Microsoft stopped supporting with security updates earlier this month. Symantec Corp, the biggest maker of PC-security software, advised customers to switch to another browser until Microsoft releases a software patch to fix the vulnerability and to use a security mitigation tool kit that Microsoft recommended and that will work with Windows XP. The US Department of Homeland Security's Computer Emergency Readiness Team issued similar advice on Monday.

Novell suit
The US Supreme Court ended a lawsuit that accused Microsoft Corp of illegally protecting its Windows computer operating system from competition 20 years ago by undercutting a rival word-processing programme.

Declining to take up a lingering antitrust case stemming from Microsoft's software dominance in the 1990s, the justices on Monday rejected without comment an appeal by Novell Inc, which once made the WordPerfect application.