IIS 6 attack could let hackers snoop on servers

18.05.2009
Security vendors are warning users of Microsoft's Internet Information Services 6 Web-server software that a new online attack could put their data at risk.

The flaw was made public Thursday, when security researcher Nikolaos Rangos of the vulnerability to the Full Disclosure security mailing list. By sending a specially crafted HTTP request to the server he was able to view and upload files on the machine. The attack takes advantage of a bug in the way that Microsoft's software processes Unicode tokens, he said.

The vulnerability , the U.S. Computer Emergency Response Team said Monday.

In a statement, Microsoft said it hadn't heard of any such attacks, but that it was investigating Rangos' claims. "We are working on a security advisory to provide customers with guidance," the company said Monday.

The bug affects IIS 6 users who have enabled the WebDAV (Web-based Distributed Authoring and Versioning) protocols, used to share documents via the Web.