When trying to load a non-video in an audio/video context the exact status code (200, 302, 404, 500, 412, 403, etc.) was disclosed via the MediaError Message. This level of information leakage is inconsistent with the standardized onerror/onsuccess disclosure and can lead to inferring login status to services or device discovery on a local network among other attacks. This vulnerability affects Firefox < 80 and Firefox for Android < 80.

A redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.

A rogue webpage could override the injected WKUserScript used by the logins autofill, this exploit could result in leaking a password for the current domain. This vulnerability affects Firefox for iOS < 28.

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.

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.

Mozilla Developer Nicolas Silva found that when using WebRender, Firefox would under certain conditions leak arbitrary GPU memory to the visible screen. The leaked memory content was visible to the user, but not observable from web content. This vulnerability affects Firefox < 77.

Uploading files which contain symlinks may have allowed an attacker to trick a user into submitting sensitive data to a malicious website. This vulnerability affects Firefox < 115.

When Firefox is configured to block storage of all cookies, it was still possible to store data in localstorage by using an iframe with a source of 'about:blank'. This could have led to malicious websites storing tracking data without permission. This vulnerability affects Firefox < 115.

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.

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.

A malicious extension with the 'search' permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this cross-origin request could have been read by the extension, allowing a same-origin policy bypass by the extension, which should not have cross-origin permissions. This cross-origin request was made without cookies, so the sensitive information disclosed by the violation was limited to local-network resources or resources that perform IP-based authentication. This vulnerability affects Firefox < 87.

The file scheme of URLs would be hidden, resulting in potential spoofing of a website's address in the location bar This vulnerability affects Focus for iOS < 126.

Different techniques existed to obscure the fullscreen notification in Firefox for Android. These could have led to potential user confusion and spoofing attacks. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 126.

Dragging Javascript URLs to the address bar could cause them to be loaded, bypassing restrictions and security protections This vulnerability affects Firefox for iOS < 124.

If an insecure element was added to a page after a delay, Firefox would not replace the secure icon with a mixed content security status This vulnerability affects Firefox for iOS < 124.

A flaw in handling fullscreen transitions may have inadvertently caused the application to become stuck in fullscreen mode when a modal dialog was opened during the transition. This issue left users unable to exit fullscreen mode using standard actions like pressing "Esc" or accessing right-click menus, resulting in a disrupted browsing experience until the browser is restarted. *This bug only affects the application when running on macOS. Other operating systems are unaffected.* This vulnerability affects Firefox < 133, Firefox ESR < 128.5, Thunderbird < 133, and Thunderbird < 128.5.

The executable file warning was not presented when downloading .library-ms files. *Note: This issue only affected Windows operating systems. Other operating systems are unaffected.* This vulnerability affects Firefox < 133, Firefox ESR < 128.5, Thunderbird < 133, and Thunderbird < 128.5.

A compromised child process could have injected XBL Bindings into privileged CSS rules, resulting in arbitrary code execution and a sandbox escape. This vulnerability affects Firefox < 70.

When using an invalid protocol scheme, an attacker could spoof the address bar. *Note: This issue only affected Android operating systems. Other operating systems are unaffected.* *Note: This issue is a different issue from CVE-2025-0244. This vulnerability affects Firefox < 134.

In addition to detecting when a user was taking a screenshot (XXX), a website was able to overlay the 'My Shots' button that appeared, and direct the user to a replica Firefox Screenshots page that could be used for phishing. This vulnerability affects Firefox < 127.

A local attacker can trick the Mozilla Maintenance Service into applying an unsigned update file by pointing the service at an update file on a malicious SMB server. The update file can be replaced after the signature check, before the use, because the write-lock requested by the service does not work on a SMB server. *Note: This attack requires local system access and only affects Windows. Other operating systems are not affected.* This vulnerability affects Firefox < 112, Firefox ESR < 102.10, and Thunderbird < 102.10.

Similar to CVE-2023-28163, this time when choosing 'Save Link As', suggested filenames containing environment variable names would have resolved those in the context of the current user. *This bug only affects Firefox and Thunderbird on Windows. Other versions of Firefox and Thunderbird are unaffected.* This vulnerability affects Firefox < 112, Firefox ESR < 102.10, and Thunderbird < 102.10.

A newline in a filename could have been used to bypass the file extension security mechanisms that replace malicious file extensions such as .lnk with .download. This could have led to accidental execution of malicious code. *This bug only affects Firefox and Thunderbird on Windows. Other versions of Firefox and Thunderbird are unaffected.* This vulnerability affects Firefox < 112, Firefox ESR < 102.10, and Thunderbird < 102.10.

Different techniques existed to obscure the fullscreen notification in Firefox and Focus for Android. These could have led to potential user confusion and spoofing attacks. *This bug only affects Firefox and Focus for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox for Android < 112 and Focus for Android < 112.

An invalid downcast from `nsHTMLDocument` to `nsIContent` could have lead to undefined behavior. This vulnerability affects Firefox < 110.

Passing invalid data could have led to invalid wasm values being created, such as arbitrary integers turning into pointer values. This vulnerability affects Firefox < 124.

Accessing a non-secure HTTP site that uses a non-existent port may cause the SSL padlock icon in the location URL bar to, misleadingly, appear secure. This vulnerability affects Firefox for iOS < 133.

Under certain circumstances, a user opt-in setting that Focus should require authentication before use could have been be bypassed. This vulnerability affects Firefox < 134.

A specially crafted filename containing a large number of spaces could obscure the file's extension when displayed in the download dialog. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 131.

The issue was addressed with improved checks. This issue is fixed in tvOS 18.1, iOS 18.1 and iPadOS 18.1, iOS 17.7.1 and iPadOS 17.7.1, macOS Ventura 13.7.1, macOS Sonoma 14.7.1, watchOS 11.1, visionOS 2.1. Processing a maliciously crafted font may result in the disclosure of process memory.

Insufficient policy enforcement in Navigation in Google Chrome prior to 85.0.4183.83 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium)