Mozilla Firefox allows for cookies to be set with a null domain (aka "domainless cookies"), which allows remote attackers to pass information between arbitrary domains and track user activity, as demonstrated by the domain attribute in the document.cookie variable in a javascript: window.

Argument injection vulnerability in Microsoft Internet Explorer, when running on systems with Firefox installed and certain URIs registered, allows remote attackers to conduct cross-browser scripting attacks and execute arbitrary commands via shell metacharacters in a (1) FirefoxURL or (2) FirefoxHTML URI, which are inserted into the command line that is created when invoking firefox.exe. NOTE: it has been debated as to whether the issue is in Internet Explorer or Firefox. As of 20070711, it is CVE's opinion that IE appears to be failing to properly delimit the URL argument when invoking Firefox, and this issue could arise with other protocol handlers in IE as well. However, Mozilla has stated that it will address the issue with a "defense in depth" fix that will "prevent IE from sending Firefox malicious data."

Unspecified vulnerability in Mozilla Firefox allows remote attackers to execute arbitrary code via unspecified vectors involving Javascript errors. NOTE: this might be the same issue as CVE-2007-2175.

Mozilla Firefox does not warn the user about HTTP elements on an HTTPS page when the HTTP elements are dynamically created by a delayed document.write, which allows remote attackers to supply unauthenticated content and conduct phishing attacks.

Cross-site scripting (XSS) vulnerability in the (1) Sage before 1.3.10, and (2) Sage++ extensions for Firefox, allows remote attackers to inject arbitrary web script or HTML via a "<SCRIPT/=''SRC='" sequence in an RSS feed, a different vulnerability than CVE-2006-4712.

Netscape Navigator 7.0.2 and Mozilla allows remote attackers to access cookie information in a different domain via an HTTP request for a domain with an extra . (dot) at the end.