Microsoft Security Advisory MS01-022 - The Microsoft Data Access Component Internet Publishing Provider provides access to WebDAV resources over the Internet. It contains an implementation flaw causing it to handle all requests in the security context of the user. As a result, if a user browsed to a web page or opened an HTML e-mail that contained script, that script could access web-based resources as the user. It is likely that at a minimum, the attacker could browse the user's intranet, and access web-based e-mail as well. Microsoft FAQ on this issue available here.
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