An anonymous reader writes "A new XSS vulnerability was found in Facebook, allowing executable code to be injected in a user's profile; this compromises the security of both the profile owner and all profile viewers. The article includes a sketch of the attack, a white paper that gives a detailed explanation of how such an attack can be used, and a video demo. Facebook is set up so that once a single hidden value has been obtained, any form can be submitted with that user's credentials. One would think that XSS vulnerabilities are common and serious enough that Facebook would have set up their site so that the entire site is not laid open by a single attack. (The article does not disclose the location of the XSS hole since it has not yet been patched.)"
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