Microsoft IIS web server under attack from hackers

Microsoft has updated a security advisory concerning vulnerabilities in its Internet Information Services (IIS) web server, confirming that "limited" attacks were using publicly available exploit code.

The attacks are targeting flaws in the FTP service in Microsoft IIS 5.0 and could allow remote execution attacks or denial of service (DoS) attacks in IIS 5.0 as well as 5.1, 6.0 or 7.0.

Microsoft said it was aware that detailed exploit code had been published for the vulnerabilities, and was "actively monitoring this situation to keep customers informed and to provide customer guidance as necessary."

Microsoft said in the advisory: "These vulnerabilities were not responsibly disclosed to Microsoft and may put computer users at risk."

Tomorrow's Patch Tuesday has come too soon to fix the IIS vulnerabilities in question, but Microsoft said it would take the appropriate action, which could mean a security update released for a future Patch Tuesday or an out-of-cycle security update.