The International Domain Name (IDN) support in Firefox 1.0, Camino .8.5, and Mozilla before 1.7.6 allows remote attackers to spoof domain names using punycode encoded domain names that are decoded in URLs and SSL certificates in a way that uses homograph characters from other character sets, which facilitates phishing attacks.
Firefox 1.0 does not prevent the user from dragging an executable file to the desktop when it has an image/gif content type but has a dangerous extension such as .bat or .exe, which allows remote attackers to bypass the intended restriction and execute arbitrary commands via malformed GIF files that can still be parsed by the Windows batch file parser, aka "firedragging."
String handling functions in Mozilla 1.7.3, Firefox 1.0, and Thunderbird before 1.0.2, such as the nsTSubstring_CharT::Replace function, do not properly check the return values of other functions that resize the string, which allows remote attackers to cause a denial of service and possibly execute arbitrary code by forcing an out-of-memory state that causes a reallocation to fail and return a poi ...
Thunderbird 0.6 through 0.9 and Mozilla 1.7 through 1.7.3 does not obey the network.cookie.disableCookieForMailNews preference, which could allow remote attackers bypass the user's intended privacy and security policy by using cookies in e-mail messages.
Firefox before 1.0 and Mozilla before 1.7.5, when configured to use a proxy, respond to 407 proxy auth requests from arbitrary servers, which allows remote attackers to steal NTLM or SPNEGO credentials.