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.

Gecko-based browsers, including Mozilla Firefox before 2.0.0.12 and SeaMonkey before 1.1.8, modify the .href property of stylesheet DOM nodes to the final URI of a 302 redirect, which might allow remote attackers to bypass the Same Origin Policy and read sensitive information from the original URL, such as with Single-Signon systems.

If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs. 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.

Bugzilla before 3.0.11, 3.2.x before 3.2.6, 3.4.x before 3.4.5, and 3.5.x before 3.5.3 does not block access to files and directories that are used by custom installations, which allows remote attackers to obtain sensitive information via requests for (1) CVS/, (2) contrib/, (3) docs/en/xml/, (4) t/, or (5) old-params.txt.

content/html/document/src/nsHTMLDocument.cpp in Mozilla Firefox 3.0.x before 3.0.15 and 3.5.x before 3.5.4 allows user-assisted remote attackers to bypass the Same Origin Policy and read an arbitrary content selection via the document.getSelection function.

A permission leak could have occurred from a trusted site to an untrusted site via `embed` or `object` elements. This vulnerability affects Firefox < 132, Firefox ESR < 128.4, Firefox ESR < 115.17, Thunderbird < 128.4, and Thunderbird < 132.

Video frames could have been leaked between origins in some situations. This vulnerability affects Firefox < 132, Firefox ESR < 128.4, Firefox ESR < 115.17, Thunderbird < 128.4, and Thunderbird < 132.

Mozilla Firefox before 3.0.11 and SeaMonkey before 1.1.17 associate local documents with external domain names located after the file:// substring in a URL, which allows user-assisted remote attackers to read arbitrary cookies via a crafted HTML document, as demonstrated by a URL with file://example.com/C:/ at the beginning.

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.

When deriving an identifier for an email message, uninitialized memory was used in addition to the message contents. This vulnerability affects Thunderbird < 68.5.

Mozilla Firefox before 3.0.9 and SeaMonkey before 1.1.17 allow user-assisted remote attackers to obtain sensitive information via a web page with an embedded frame, which causes POST data from an outer page to be sent to the inner frame's URL during a SAVEMODE_FILEONLY save of the inner frame.

Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

On some systems—depending on the graphics settings and drivers—it was possible to force an out-of-bounds read and leak memory data into the images created on the canvas element. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

`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.

Browser tab titles were being leaked by GNOME to system logs. This could potentially expose the browsing habits of users running in a private tab. This vulnerability affects Firefox < 121.

If an image had not loaded correctly (such as when it is not actually an image), it could be dragged and dropped cross-domain, resulting in a cross-origin information leak. This vulnerability affects Firefox < 71.

Heap-based buffer overflow in the mozilla::gfx::CopyRect function in Mozilla Firefox before 36.0, Firefox ESR 31.x before 31.5, and Thunderbird before 31.5 allows remote attackers to obtain sensitive information from uninitialized process memory via a malformed SVG graphic.

WebRTC in Firefox will honor persisted permissions given to sites for access to microphone and camera resources even when in a third-party context. In light of recent high profile vulnerabilities in other software, a decision was made to no longer persist these permissions. This avoids the possibility of trusted WebRTC resources being invisibly embedded in web content and abusing permissions previously given by users. Users will now be prompted for permissions on each use. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.

Navigation events were not fully adhering to the W3C's "Navigation-Timing Level 2" draft specification in some instances for the unload event, which restricts access to detailed timing attributes to only be same-origin. This resulted in potential cross-origin information exposure of history through timing side-channel attacks. This vulnerability affects Firefox < 69, Thunderbird < 68.1, Thunderbird < 60.9, Firefox ESR < 60.9, and Firefox ESR < 68.1.

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.

The HTTP Alternative Services header, Alt-Svc, can be used by a malicious site to scan all TCP ports of any host that the accessible to a user when web content is loaded. This vulnerability affects Firefox < 68.

Encrypted S/MIME parts in a crafted multipart/alternative message can leak plaintext when included in a a HTML reply/forward. This vulnerability affects Thunderbird < 68.1 and Thunderbird < 60.9.

A hyperlink using the res: protocol can be used to open local files at a known location in Internet Explorer if a user approves execution when prompted. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 67.

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 affects Firefox < 141, Firefox ESR < 115.26, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1.

A hyperlink using protocols associated with Internet Explorer, such as IE.HTTP:, can be used to open local files at a known location with Internet Explorer if a user approves execution when prompted. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 67.0.2.

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

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

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.

An existing mitigation of timing side-channel attacks is insufficient in some circumstances. This issue is addressed in Network Security Services (NSS) 3.26.1. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

When recording the screen while in Private Browsing on Firefox for Android the address bar and keyboard were not hidden, potentially leaking sensitive information. *This bug only affects Firefox for Android. Other operating systems are unaffected.* This vulnerability affects Firefox for Android < 112 and Focus for Android < 112.

When following a redirect to a publicly accessible web extension file, the URL may have been translated to the actual local path, leaking potentially sensitive information. This vulnerability affects Firefox < 111.

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.

Microsoft introduced a new feature in Windows 10 known as Cloud Clipboard which, if enabled, will record data copied to the clipboard to the cloud, and make it available on other computers in certain scenarios. Applications that wish to prevent copied data from being recorded in Cloud History must use specific clipboard formats; and Firefox before versions 94 and ESR 91.3 did not implement them. This could have caused sensitive data to be recorded to a user's Microsoft account. *This bug only affects Firefox for Windows 10+ with Cloud Clipboard enabled. Other operating systems are unaffected.*. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

WebExtensions with the appropriate permissions can attach content scripts to Mozilla sites such as accounts.firefox.com and listen to network traffic to the site through the "webRequest" API. For example, this allows for the interception of username and an encrypted password during login to Firefox Accounts. This issue does not expose synchronization traffic directly and is limited to the process of user login to the website and the data displayed to the user once logged in. This vulnerability affects Firefox < 60.

Thunderbird ignored the configuration to require STARTTLS security for an SMTP connection. A MITM could perform a downgrade attack to intercept transmitted messages, or could take control of the authenticated session to execute SMTP commands chosen by the MITM. If an unprotected authentication method was configured, the MITM could obtain the authentication credentials, too. This vulnerability affects Thunderbird < 91.2.

If the "app.support.baseURL" preference is changed by a malicious local program to contain HTML and script content, this content is not sanitized. It will be executed if a user loads "chrome://browser/content/preferences/in-content/preferences.xul" directly in a tab and executes a search. This stored preference is also executed whenever an EME video player plugin displays a CDM-disabled message as a notification message. This vulnerability affects Firefox < 59.

Regular expressions used to filter out forbidden properties and values from style directives in calls to <code>console.log</code> weren't accounting for external URLs. Data could then be potentially exfiltrated from the browser. This vulnerability affects Firefox < 109, Thunderbird < 102.7, and Firefox ESR < 102.7.

Due to the Firefox GTK wrapper code's use of text/plain for drag data and GTK treating all text/plain MIMEs containing file URLs as being dragged a website could arbitrarily read a file via a call to <code>DataTransfer.setData</code>. This vulnerability affects Firefox < 109, Thunderbird < 102.7, and Firefox ESR < 102.7.

Per origin notification permissions were being stored in a way that didn't take into account what browsing context the permission was granted in. This lead to the possibility of notifications to be displayed during different browsing sessions.<br>*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 109.

A compromised web child process could disable web security opening restrictions, leading to a new child process being spawned within the <code>file://</code> context. Given a reliable exploit primitive, this new process could be exploited again leading to arbitrary file read. This vulnerability affects Firefox < 109.

WebExtension content scripts can be loaded into about: pages in some circumstances, in violation of the permissions granted to extensions. This could allow an extension to interfere with the loading and usage of these pages and use capabilities that were intended to be restricted from extensions. This vulnerability affects Firefox < 64.

A same-origin policy violation allowing the theft of cross-origin URL entries when using a meta http-equiv="refresh" on a page to cause a redirection to another site using performance.getEntries(). This is a same-origin policy violation and could allow for data theft. This vulnerability affects Firefox < 62, Firefox ESR < 60.2, and Thunderbird < 60.2.1.

When an extension with the proxy permission registered to receive <all_urls>, the proxy.onRequest callback was not triggered for view-source URLs. While web content cannot navigate to such URLs, a user opening View Source could have inadvertently leaked their IP address. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.

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.

Mozilla Firefox before 49.0, Firefox ESR 45.x before 45.4, and Thunderbird < 45.4 rely on unintended expiration dates for Preloaded Public Key Pinning, which allows man-in-the-middle attackers to spoof add-on updates by leveraging possession of an X.509 server certificate for addons.mozilla.org signed by an arbitrary built-in Certification Authority.

Mozilla Firefox before 48.0 mishandles changes from 'INPUT type="password"' to 'INPUT type="text"' within a single Session Manager session, which might allow attackers to discover cleartext passwords by reading a session restoration file.

Web content could access information in the HTTP cache if e10s is disabled. This can reveal some visited URLs and the contents of those pages. This issue affects Firefox 48 and 49. This vulnerability affects Firefox < 49.0.2.

Mozilla Firefox before 49.0 does not properly restrict the scheme in favicon requests, which might allow remote attackers to obtain sensitive information via unspecified vectors, as demonstrated by a jar: URL for a favicon resource.