toolkit/components/passwordmgr/src/nsLoginManagerPrompter.js in the asynchronous Authorization Prompt implementation in Mozilla Firefox 3.6 before 3.6.2 does not properly handle concurrent authorization requests from multiple web sites, which might allow remote web servers to spoof an authorization dialog and capture credentials by demanding HTTP authentication in opportunistic circumstances.
www.mandriva.com/security/advisories?name=MDVSA-2010:070
www.mozilla.org/security/announce/2010/mfsa2010-15.html
www.securityfocus.com/bid/38918
www.vupen.com/english/advisories/2010/0692
bugzilla.mozilla.org/show_bug.cgi?id=537862
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A8281