Unpatched IIS Flaw Being Exploited
by Tony Bradley • September 4, 2009 • Blog
Are you running IIS? If so, you should be aware of an exploit currently being used by attackers in the wild.
The exploit primarily affects older versions of IIS. The initial exploit code targets IIS 5.0 running on Windows 2000 and could allow the attacker to take complete control of the IIS server. Newer exploit code was subsequently released which affects IIS 5.0, 5.1, 6.0 and 7.0, and could affect users running IIS on Windows XP and Windows Server 2003. The newer exploit code results in a DoS (denial-of-service).
Both attacks rely on IIS also running FTP and that the attacker has some access to be able to write to the server. Microsoft will be releasing the September Security Bulletins this coming Tuesday, but this threat is just emerging and is not expected to be included as one of the regularly scheduled patches this month.
Microsoft has issued a Security Advisory related to these attacks which includes mitigating factors and workarounds you can use to protect your IIS server pending a more permanent fix from Microsoft.