//////////////////////////////////////////////////////////////////// //====================>> Security Advisory <<=====================// //////////////////////////////////////////////////////////////////// -------------------------------------------------------------------- -----[ IIS 5.x/6.0 WebDAV (XML parser) attribute blowup DoS -------------------------------------------------------------------- --[ Author: Amit Klein --[ Release Date: October 12, 2004 --[ Products: Microsoft IIS/5.0 (Windows/2000) Microsoft IIS/5.1 (Windows XP) Microsoft IIS/6.0 (Windows/2003) --[ Severity: High --[ Description An attacker can craft a malicious WebDAV PROPFIND request, which uses XML attributes in a way that inflicts a denial of service condition on the target machine (IIS web server). The result of this attack is that the XML parser consumes all the CPU resources for a long period of time (from seconds to minutes, depending on the size of the payload). In our experiments, we were able to send attacks (of few hunderd KBs) that caused the target machines to consume 100% CPU for several minutes. --[ Solution Microsoft security bulletin MS04-030 (October 12th, 2004) http://www.microsoft.com/technet/security/bulletin/MS04-030.mspx --[ Acknowledgements To Ory Segal (Watchfire), for the his help with applying this attack to IIS.