Service Workers should not be able to infer information about opaque cross-origin responses; but timing information for cross-origin media combined with Range requests might have allowed them to determine the presence or length of a media file. This vulnerability affects Firefox ESR < 102.5, Thunderbird < 102.5, and Firefox < 107.

Keyboard events reference strings like "KeyA" that were at fixed, known, and widely-spread addresses. Cache-based timing attacks such as Prime+Probe could have possibly figured out which keys were being pressed. This vulnerability affects Firefox ESR < 102.5, Thunderbird < 102.5, and Firefox < 107.

The MediaError message property should be consistent to avoid leaking information about cross-origin resources; however for a same-site cross-origin resource, the message could have leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 102.

The <code>Content-Security-Policy-Report-Only</code> header could allow an attacker to leak a child iframe's unredacted URI when interaction with that iframe triggers a redirect. This vulnerability affects Firefox < 110, Thunderbird < 102.8, and Firefox ESR < 102.8.

When dragging and dropping an image cross-origin, the image's size could potentially be leaked. This behavior was shipped in 109 and caused web compatibility problems as well as this security concern, so the behavior was disabled until further review. This vulnerability affects Firefox < 110.

An attacker could have exploited a timing attack by sending a large number of allowCredential entries and detecting the difference between invalid key handles and cross-origin key handles. This could have led to cross-origin account linking in violation of WebAuthn goals. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

`EncryptingOutputStream` was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode. This vulnerability affects Firefox ESR < 115.6 and Firefox < 121.

A vulnerability exists where if a user opens a locally saved HTML file, this file can use file: URIs to access other files in the same directory or sub-directories if the names are known or guessed. The Fetch API can then be used to read the contents of any files stored in these directories and they may uploaded to a server. It was demonstrated that in combination with a popular Android messaging app, if a malicious HTML attachment is sent to a user and they opened that attachment in Firefox, due to that app's predictable pattern for locally-saved file names, it is possible to read attachments the victim received from other correspondents. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

A use-after-free vulnerability in SVG Animation has been discovered. An exploit built on this vulnerability has been discovered in the wild targeting Firefox and Tor Browser users on Windows. This vulnerability affects Firefox < 50.0.2, Firefox ESR < 45.5.1, and Thunderbird < 45.5.1.

During iframe navigation, certain pages did not have their FeaturePolicy fully initialized leading to a bypass that leaked device permissions into untrusted subdocuments. This vulnerability affects Firefox ESR < 102.3, Thunderbird < 102.3, and Firefox < 105.

The N-able PassPortal extension before 3.29.2 for Chrome inserts sensitive information into a log file.

The browser could have been confused into transferring a screen sharing state into another tab, which would leak unintended information. This vulnerability affects Firefox < 85.

When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted, and the content of that error may have revealed information about the resource. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

An ambiguous file picker design could have confused users who intended to select and upload a single file into uploading a whole directory. This was addressed by adding a new prompt. This vulnerability affects Firefox < 85.

When processing a redirect with a conflicting Referrer-Policy, Firefox would have adopted the redirect's Referrer-Policy. This would have potentially resulted in more information than intended by the original origin being provided to the destination of the redirect. This vulnerability affects Firefox < 86.

If an attacker is able to alter specific about:config values (for example malware running on the user's computer), the Devtools remote debugging feature could have been enabled in a way that was unnoticable to the user. This would have allowed a remote attacker (able to make a direct network connection to the victim) to monitor the user's browsing activity and (plaintext) network traffic. This was addressed by providing a visual cue when Devtools has an open network socket. This vulnerability affects Firefox < 87.

Information disclosure in the Widget: Cocoa component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Firefox behaved slightly differently for already known resources when loading CSS resources involving CSS variables. This could have been used to probe the browser history. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

When receiving an HTML email that contained an <code>iframe</code> element, which used a <code>srcdoc</code> attribute to define the inner HTML document, remote objects specified in the nested document, for example images or videos, were not blocked. Rather, the network was accessed, the objects were loaded and displayed. This vulnerability affects Thunderbird < 102.2.1 and Thunderbird < 91.13.1.

When generating the assembly code for <code>MLoadTypedArrayElementHole</code>, an incorrect AliasSet was used. In conjunction with another vulnerability this could have been used for an out of bounds memory read. This vulnerability affects Thunderbird < 91.8, Firefox < 99, and Firefox ESR < 91.8.

The sourceMapURL feature in devtools was missing security checks that would have allowed a webpage to attempt to include local files or other files that should have been inaccessible. This vulnerability affects Firefox < 99.

An attacker could, via a specially crafted multipart response, execute arbitrary JavaScript under the `resource://pdf.js` origin. This could allow them to access cross-origin PDF content. This access is limited to "same site" documents by the Site Isolation feature on desktop clients, but full cross-origin access is possible on Android versions. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131.

An attacker could, via a specially crafted multipart response, execute arbitrary JavaScript under the `resource://devtools` origin. This could allow them to access cross-origin JSON content. This access is limited to "same site" documents by the Site Isolation feature on desktop clients, but full cross-origin access is possible on Android versions. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131.

Previously Firefox for macOS and Linux would download temporary files to a user-specific directory in <code>/tmp</code>, but this behavior was changed to download them to <code>/tmp</code> where they could be affected by other local users. This behavior was reverted to the original, user-specific directory. <br>*This bug only affects Firefox for macOS and Linux. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 91.7 and Thunderbird < 91.7.

ANGLE failed to initialize parameters which lead to reading from uninitialized memory. This could be leveraged to leak sensitive data from memory. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, Firefox ESR < 128.1, Thunderbird < 128.1, and Thunderbird < 115.14.

Calling `PK11_Encrypt()` in NSS using CKM_CHACHA20 and the same buffer for input and output can result in plaintext on an Intel Sandy Bridge processor. In Firefox this only affects the QUIC header protection feature when the connection is using the ChaCha20-Poly1305 cipher suite. The most likely outcome is connection failure, but if the connection persists despite the high packet loss it could be possible for a network observer to identify packets as coming from the same source despite a network path change. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, and Firefox ESR < 128.1.

An attacker could have caused a use-after-free in the JavaScript engine to read memory in the JavaScript string section of the heap. This vulnerability affects Firefox < 127.

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.

By generally accepting and passing resource handles across processes, a compromised content process might have confused higher privileged processes to interact with handles that the unprivileged process should not have access to.<br>*This bug only affects Firefox for Windows and MacOS. Other operating systems are unaffected.*. This vulnerability affects Firefox < 96.

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 reading from areas partially or fully outside the source resource with WebGL's <code>copyTexSubImage</code> method, the specification requires the returned values be zero. Previously, this memory was uninitialized, leading to potentially sensitive data disclosure. This vulnerability affects Thunderbird < 68.7.0, Firefox ESR < 68.7, and Firefox < 75.

When a Web Extension had the all-urls permission and made a fetch request with a mode set to 'same-origin', it was possible for the Web Extension to read local files. This vulnerability affects Firefox < 74.

For native-to-JS bridging, the app requires a unique token to be passed that ensures non-app code can't call the bridging functions. That token was being used for JS-to-native also, but it isn't needed in this case, and its usage was also leaking this token. This vulnerability affects Firefox for iOS < 25.

When processing an email message with an ill-formed envelope, Thunderbird could read data from a random memory location. This vulnerability affects Thunderbird < 68.5.

If a user saved passwords before Thunderbird 60 and then later set a master password, an unencrypted copy of these passwords is still accessible. This is because the older stored password file was not deleted when the data was copied to a new format starting in Thunderbird 60. The new master password is added only on the new file. This could allow the exposure of stored password data outside of user expectations. This vulnerability affects Thunderbird < 68.5.

Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Information disclosure, mitigation bypass in the Settings UI component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.

The Web workers implementation in Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, and SeaMonkey before 2.24 allows remote attackers to bypass the Same Origin Policy and obtain sensitive authentication information via vectors involving error messages.

Information disclosure due to uninitialized memory in Firefox and Firefox Focus for Android. This vulnerability was fixed in Firefox 148.

Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

After requesting multiple permissions, and closing the first permission panel, subsequent permission panels will be displayed in a different position but still record a click in the default location, making it possible to trick a user into accepting a permission they did not want to. *This bug only affects Firefox on Linux. Other operating systems are unaffected.*. This vulnerability affects Firefox < 91 and Thunderbird < 91.

Due to incorrect JIT optimization, we incorrectly interpreted data from the wrong type of object, resulting in the potential leak of a single bit of memory. This vulnerability affects Firefox < 91 and Thunderbird < 91.

Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.

The JavaScript engine did not handle closed generators correctly and it was possible to resume them leading to a nullptr deref. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

On 64-bit platforms IonMonkey-JIT only wrote 32 bits of the 64-bit return value space on the stack. Baseline-JIT, however, read the entire 64 bits. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

Mozilla Firefox before 21.0, Firefox ESR 17.x before 17.0.6, Thunderbird before 17.0.6, and Thunderbird ESR 17.x before 17.0.6 do not properly initialize data structures for the nsDOMSVGZoomEvent::mPreviousScale and nsDOMSVGZoomEvent::mNewScale functions, which allows remote attackers to obtain sensitive information from process memory via a crafted web site.

In certain cases, SNI could have been sent unencrypted even when encrypted DNS was enabled. This vulnerability was fixed in Firefox 139 and Thunderbird 139.

Some websites have a feature "Show Password" where clicking a button will change a password field into a textbook field, revealing the typed password. If, when using a software keyboard that remembers user input, a user typed their password and used that feature, the type of the password field was changed, resulting in a keyboard layout change and the possibility for the software keyboard to remember the typed password. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.