Mozilla Firefox — свободный браузер на движке Gecko

Firefox before 1.0.3 and Mozilla Suite before 1.7.7, when blocking a popup, allows remote attackers to execute arbitrary code via a javascript: URL that is executed when the user selects the "Show javascript" option.

Firefox before 1.0.1 and Mozilla before 1.7.6 does not restrict xsl:include and xsl:import tags in XSLT stylesheets to the current domain, which allows remote attackers to determine the existence of files on the local system.

Firefox before 1.0.3 and Mozilla Suite before 1.7.7 allows remote attackers to execute arbitrary script in other domains via a setter function for a variable in the target domain, which is executed when the user visits that domain, aka "Cross-site scripting through global scope pollution."

Firefox before 1.0.1 and Mozilla before 1.7.6, when displaying the HTTP Authentication dialog, do not change the focus to the tab that generated the prompt, which could facilitate spoofing and phishing attacks.

Firefox before 1.0 and Mozilla before 1.7.5 allow remote attackers to obtain sensitive data from the clipboard via Javascript that generates a middle-click event on systems for which a middle-click performs a paste operation.

Firefox before 1.0.1 and Mozilla Suite before 1.7.6 use a predictable filename for the plugin temporary directory, which allows local users to delete arbitrary files of other users via a symlink attack on the plugtmp directory.

Firefox before 1.0.3, Mozilla Suite before 1.7.7, and Netscape 7.2 allows remote attackers to execute arbitrary script and code via a new search plugin using sidebar.addSearchEngine, aka "Firesearching 1."

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 pointer to a fixed address, which leads to heap corruption.

The Form Fill feature in Firefox before 1.0.1 allows remote attackers to steal potentially sensitive information via an input control that monitors the values that are generated by the autocomplete capability.

Firefox 0.9, Thunderbird 0.6 and other versions before 0.9, and Mozilla 1.7 before 1.7.5 save temporary files with world-readable permissions, which allows local users to read certain web content or attachments that belong to other users, e.g. content that is managed by helper applications such as PDF.