When importing resources using Web Workers, error messages would distinguish the difference between <code>application/javascript</code> responses and non-script responses. This could have been abused to learn information cross-origin. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.
If a document created a sandboxed iframe without <code>allow-scripts</code>, and subsequently appended an element to the iframe's document that e.g. had a JavaScript event handler - the event handler would have run despite the iframe's sandbox. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.
If a user was convinced to drag and drop an image to their desktop or other folder, the resulting object could have been changed into an executable script which would have run arbitrary code after the user clicked on it. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.
If a user installed an extension of a particular type, the extension could have auto-updated itself and while doing so, bypass the prompt which grants the new version the new requested permissions. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.
Mozilla developers Calixte Denizet, Kershaw Chang, Christian Holler, Jason Kratzer, Gabriele Svelto, Tyson Smith, Simon Giesecke, and Steve Fink reported memory safety bugs present in Firefox 95 and Firefox ESR 91.4. 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 ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Malicious websites could have confused Firefox into showing the wrong origin when asking to launch a program and handling an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
After accepting an untrusted certificate, handling an empty pkcs7 sequence as part of the certificate data could have lead to a crash. This crash is believed to be unexploitable. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Securitypolicyviolation events could have leaked cross-origin information for frame-ancestors violations. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
When navigating from inside an iframe while requesting fullscreen access, an attacker-controlled tab could have made the browser unable to leave fullscreen mode. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
When inserting text while in edit mode, some characters might have lead to out-of-bounds memory access causing a potentially exploitable crash. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
When resizing a popup while requesting fullscreen access, the popup would have become unable to leave fullscreen mode. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Certain network request objects were freed too early when releasing a network request handle. This could have lead to a use-after-free causing a potentially exploitable crash. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Applying a CSS filter effect could have accessed out of bounds memory. This could have lead to a heap-buffer-overflow causing a potentially exploitable crash. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
Constructing audio sinks could have lead to a race condition when playing audio files and closing windows. This could have lead to a use-after-free causing a potentially exploitable crash. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
An OpenPGP digital signature includes information about the date when the signature was created. When displaying an email that contains a digital signature, the email's date will be shown. If the dates were different, then Thunderbird didn't report the email as having an invalid signature. If an attacker performed a replay attack, in which an old email with old contents are resent at a later time, it could lead the victim to believe that the statements in the email are current. Fixed versions of Thunderbird will require that the signature's date roughly matches the displayed date of the email. This vulnerability affects Thunderbird < 102 and
If an object prototype was corrupted by an attacker, they would have been able to set undesired attributes on a JavaScript object, leading to privileged code execution. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.
When displaying the sender of an email, and the sender name contained the Braille Pattern Blank space character multiple times, Thunderbird would have displayed all the spaces. This could have been used by an attacker to send an email message with the attacker's digital signature, that was shown with an arbitrary sender email address chosen by the attacker. If the sender name started with a false email address, followed by many Braille space characters, the attacker's email address was not visible. Because Thunderbird compared the invisible sender address with the signature's email address, if the signing key or certificate was accepted by Th
If an attacker was able to corrupt the methods of an Array object in JavaScript via prototype pollution, they could have achieved execution of attacker-controlled JavaScript code in a privileged context. This vulnerability affects Firefox ESR < 91.9.1, Firefox < 100.0.2, Firefox for Android < 100.3.0, and Thunderbird < 91.9.1.
An attacker could have sent a message to the parent process where the contents were used to double-index into a JavaScript object, leading to prototype pollution and ultimately attacker-controlled JavaScript executing in the privileged parent process. This vulnerability affects Firefox ESR < 91.9.1, Firefox < 100.0.2, Firefox for Android < 100.3.0, and Thunderbird < 91.9.1.