A serious vulnerability exists within the WebDAV component of Microsoft Internet Information Services (IIS) Web server. WebDAV stands for "Web-based Distrbuted Authoring and Versioning". WebDAV extensions are used by administrators to manage and edit Web content remotely. WebDAV is enabled by default on IIS 5 installations, and no authentication or special privileges are required for remote exploitation.

It is possible for remote attackers to run arbitrary code on vulnerable Web servers. This vulnerability is currently being exploited in the wild, and X-Force has verified the existence of a functional exploit tool. This vulnerability is in itself very serious, but the existence of robust exploits in the wild dictates that fixes or temporary workarounds should be applied immediately.

Although it is possible to disable WebDAV, doing so requires manually creating a specific registry key. The IIS Lockdown Tool from Microsoft may or may not turn off WebDAV, depending on the server template selected at installation time.