In unusual circumstances, selecting text could cause text selection caching to behave incorrectly, leading to a crash. This vulnerability affects Firefox < 99.
Mozilla developers and community members Randell Jesup, Sebastian Hengst, and the Mozilla Fuzzing Team reported memory safety bugs present in Firefox 98. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 99.
Mozilla developers and community members Nika Layzell, Andrew McCreight, Gabriele Svelto, and the Mozilla Fuzzing Team reported memory safety bugs present in Thunderbird 91.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 91.8, Firefox < 99, and Firefox ESR < 91.8.
Documents in deeply-nested cross-origin browsing contexts could have obtained permissions granted to the top-level origin, bypassing the existing prompt and wrongfully inheriting the top-level permissions. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
When closed or sent to the background, Firefox for Android would not properly record and persist HSTS settings.<br>*Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 100.
An improper implementation of the new iframe sandbox keyword <code>allow-top-navigation-by-user-activation</code> could lead to script execution without <code>allow-scripts</code> being present. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
Requests initiated through reader mode did not properly omit cookies with a SameSite attribute. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
The parent process would not properly check whether the Speech Synthesis feature is enabled, when receiving instructions from a child process. This vulnerability affects Thunderbird < 91.9.
When reusing existing popups Firefox would have allowed them to cover the fullscreen notification UI, which could have enabled browser spoofing attacks. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
The Performance API did not properly hide the fact whether a request cross-origin resource has observed redirects. This vulnerability affects Firefox < 100.