Mozilla Necko, as used in Firefox, SeaMonkey, and other applications, performs DNS prefetching of domain names contained in links within local HTML documents, which makes it easier for remote attackers to determine the network location of the application's user by logging DNS requests. NOTE: the vendor disputes the significance of this issue, stating "I don't think we necessarily need to worry about that case."

In private browsing mode on Firefox for Android, favicons are cached in the cache/icons folder as they are in non-private mode. This allows information leakage of sites visited during private browsing sessions. *Note: this issue only affects Firefox for Android. Desktop versions of Firefox are unaffected.*. This vulnerability affects Firefox < 63.

The DOMParser component in Mozilla Firefox before 15.0, Thunderbird before 15.0, and SeaMonkey before 2.12 loads subresources during parsing of text/html data within an extension, which allows remote attackers to obtain sensitive information by providing crafted data to privileged extension code.

The User.get method in Bugzilla/WebService/User.pm in Bugzilla 3.7.x and 4.0.x before 4.0.9, 4.1.x and 4.2.x before 4.2.4, and 4.3.x and 4.4.x before 4.4rc1 has a different outcome for a groups request depending on whether a group exists, which allows remote authenticated users to discover private group names by observing whether a call throws an error.

The format-number functionality in the XSLT implementation in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 allows remote attackers to obtain sensitive information via unspecified vectors that trigger a heap-based buffer over-read.

Bugzilla/Attachment.pm in attachment.cgi in Bugzilla 2.x and 3.x before 3.6.12, 3.7.x and 4.0.x before 4.0.9, 4.1.x and 4.2.x before 4.2.4, and 4.3.x and 4.4.x before 4.4rc1 allows remote attackers to read attachment descriptions from private bugs via an obsolete=1 insert action.

template/en/default/bug/field-events.js.tmpl in Bugzilla 3.x before 3.6.12, 3.7.x and 4.0.x before 4.0.9, 4.1.x and 4.2.x before 4.2.4, and 4.3.x and 4.4.x before 4.4rc1 generates JavaScript function calls containing private product names or private component names in certain circumstances involving custom-field visibility control, which allows remote attackers to obtain sensitive information by reading HTML source code.

Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, and SeaMonkey before 2.12 do not properly handle onLocationChange events during navigation between different https sites, which allows remote attackers to spoof the X.509 certificate information in the address bar via a crafted web page.

A combination of an external SVG image referenced on a page and the coloring of anchor links stored within this image can be used to determine which pages a user has in their history. This can allow a malicious website to query user history. Note: This issue only affects Firefox 57. Earlier releases are not affected. This vulnerability affects Firefox < 57.0.1.

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 Private Browsing mode is used, it is possible for a web worker to write persistent data to IndexedDB and fingerprint a user uniquely. IndexedDB should not be available in Private Browsing mode and this stored data will persist across multiple private browsing mode sessions because it is not cleared when exiting. This vulnerability affects Firefox ESR < 52.5.2 and Firefox < 57.0.1.

If a document's Referrer Policy attribute is set to "no-referrer" sometimes two network requests are made for "<link>" elements instead of one. One of these requests includes the referrer instead of respecting the set policy to not include a referrer on requests. This vulnerability affects Firefox < 57.

If web content on a page is dragged onto portions of the browser UI, such as the tab bar, links can be opened that otherwise would not be allowed to open. This can allow malicious web content to open a locally stored file through "file:" URLs. This vulnerability affects Firefox < 56.

Crafted CSS in an RSS feed can leak and reveal local path strings, which may contain user name. This vulnerability affects Thunderbird < 52.5.2.

A content security policy (CSP) "frame-ancestors" directive containing origins with paths allows for comparisons against those paths instead of the origin. This results in a cross-origin information leak of this path information. This vulnerability affects Firefox < 55.

The XrayWrapper implementation in Mozilla Firefox before 17.0, Thunderbird before 17.0, and SeaMonkey before 2.14 does not consider the compartment during property filtering, which allows remote attackers to bypass intended chrome-only restrictions on reading DOM object properties via a crafted web site.

The Mozilla Maintenance Service can be invoked by an unprivileged user to read 32 bytes of any arbitrary file on the local system by convincing the service that it is reading a status file provided by the Mozilla Windows Updater. The Mozilla Maintenance Service executes with privileged access, bypassing system protections against unprivileged users. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.

Same-origin policy protections can be bypassed on pages with embedded iframes during page reloads, allowing the iframes to access content on the top level page, leading to information disclosure. This vulnerability affects Thunderbird < 52.3, Firefox ESR < 52.3, and Firefox < 55.

A vulnerability where the security wrapper does not deny access to some exposed properties using the deprecated "_exposedProps_" mechanism on proxy objects. These properties should be explicitly unavailable to proxy objects. This vulnerability affects Firefox < 57.

A compromised IPC child process can escape the content sandbox and list the names of arbitrary files on the file system without user consent or interaction. This could result in exposure of private local files. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

An attacker could read 32 bits of values spilled onto the stack in a JIT compiled function. This vulnerability was fixed in Firefox 137 and Thunderbird 137.

CSP violations generated links in the console tab of the developer tools, pointing to the violating resource. This caused a DNS prefetch which leaked that a CSP violation happened. This vulnerability affects Firefox < 128 and Thunderbird < 128.

Android intent URLs given to Firefox for Android can be used to navigate from HTTP or HTTPS URLs to local "file:" URLs, allowing for the reading of local data through a violation of same-origin policy. Note: This attack only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 54.

Hashed codes of JavaScript objects are shared between pages. This allows for pointer leaks because an object's address can be discovered through hash codes, and also allows for data leakage of an object's content using these hash codes. This vulnerability affects Thunderbird < 45.7, Firefox ESR < 45.7, and Firefox < 51.

Using SVG filters that don't use the fixed point math implementation on a target iframe, a malicious page can extract pixel values from a targeted user. This can be used to extract history information and read text values across domains. This violates same-origin policy and leads to information disclosure. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Video files loaded video captions cross-origin without checking for the presence of CORS headers permitting such cross-origin use, leading to potential information disclosure for video captions. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Feed preview for RSS feeds can be used to capture errors and exceptions generated by privileged content, allowing for the exposure of internal information not meant to be seen by web content. This vulnerability affects Firefox < 51.

Proxy Auto-Config (PAC) files can specify a JavaScript function called for all URL requests with the full URL path which exposes more information than would be sent to the proxy itself in the case of HTTPS. Normally the Proxy Auto-Config file is specified by the user or machine owner and presumed to be non-malicious, but if a user has enabled Web Proxy Auto Detect (WPAD) this file can be served remotely. This vulnerability affects Firefox < 51.

The Gecko Media Plugin sandbox allows access to local files that match specific regular expressions. On OS OX, this matching allows access to some data in subdirectories of "/private/var" that could expose personal or temporary data. This has been updated to not allow access to "/private/var" and its subdirectories. Note: this issue only affects OS X. Other operating systems are not affected. This vulnerability affects Firefox < 52 and Thunderbird < 52.

The file picker dialog can choose and display the wrong local default directory when instantiated. On some operating systems, this can lead to information disclosure, such as the operating system or the local account name. This vulnerability affects Firefox < 52 and Thunderbird < 52.

Data sent with in multipart channels, such as the multipart/x-mixed-replace MIME type, will ignore the referrer-policy response header, leading to potential information disclosure for sites using this header. This vulnerability affects Firefox < 51.

A mechanism to bypass file system access protections in the sandbox to use the file picker to access different files than those selected in the file picker through the use of relative paths. This allows for read only access to the local file system. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.

A compromised web process using malicious IPC messages could have caused the privileged browser process to reveal blocks of its memory to the compromised process. This vulnerability was fixed in Firefox 144, Firefox ESR 115.29, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.

When switching between Android apps using the card carousel Firefox shows a black screen as its card image when a password-related screen was the last one being used. Prior to Firefox 144 the password edit screen was visible. This vulnerability was fixed in Firefox 144.

Information disclosure in the Networking: Cache component. This vulnerability was fixed in Firefox 143, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

Information disclosure, mitigation bypass in the Privacy component in Firefox for Android. This vulnerability was fixed in Firefox 143.

The PRNG implementation in the DNS resolver in Mozilla Firefox (aka Fennec) before 37.0 on Android does not properly generate random numbers for query ID values and UDP source ports, which makes it easier for remote attackers to spoof DNS responses by guessing these numbers, a related issue to CVE-2012-2808.

The Form Autocompletion feature in Mozilla Firefox before 36.0, Firefox ESR 31.x before 31.5, and Thunderbird before 31.5 allows remote attackers to read arbitrary files via crafted JavaScript code.

The WebRTC subsystem in Mozilla Firefox before 36.0 recognizes turns: and stuns: URIs but accesses the TURN or STUN server without using TLS, which makes it easier for man-in-the-middle attackers to discover credentials by spoofing a server and completing a brute-force attack within a short time window.

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.

In Apache Spark 2.1.0 to 2.1.2, 2.2.0 to 2.2.1, and 2.3.0, it's possible for a malicious user to construct a URL pointing to a Spark cluster's UI's job and stage info pages, and if a user can be tricked into accessing the URL, can be used to cause script to execute and expose information from the user's view of the Spark UI. While some browsers like recent versions of Chrome and Safari are able to block this type of attack, current versions of Firefox (and possibly others) do not.

The reader view will display cross-origin content when CORS headers are set to prohibit the loading of cross-origin content by a site. This could allow access to content that should be restricted in reader view. This vulnerability affects Firefox < 58.

Style editor traffic in the Developer Tools can be routed through a service worker hosted on a third party website if a user selects error links when these tools are open. This can allow style editor information used within Developer Tools to leak cross-origin. This vulnerability affects Firefox < 58.

Service workers can use redirection to avoid the tainting of cross-origin resources in some instances, allowing a malicious site to read responses which are supposed to be opaque. This vulnerability affects Firefox < 61.

The SVG Filters implementation in Mozilla Firefox before 3.6.28 and 4.x through 10.0, Firefox ESR 10.x before 10.0.3, Thunderbird before 3.1.20 and 5.0 through 10.0, Thunderbird ESR 10.x before 10.0.3, and SeaMonkey before 2.8 might allow remote attackers to obtain sensitive information from process memory via vectors that trigger an out-of-bounds read.

Mozilla Firefox 4.x through 9.0, Thunderbird 5.0 through 9.0, and SeaMonkey before 2.7 do not properly initialize data for image/vnd.microsoft.icon images, which allows remote attackers to obtain potentially sensitive information by reading a PNG image that was created through conversion from an ICO image.

Under certain circumstances, asynchronous functions could have caused a navigation to fail but expose the target URL. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Mozilla Firefox 4.x through 8.0, Thunderbird 5.0 through 8.0, and SeaMonkey before 2.6 allow remote attackers to capture keystrokes entered on a web page, even when JavaScript is disabled, by using SVG animation accessKey events within that web page.

Mozilla Firefox before 8.0 and Thunderbird before 8.0 on Mac OS X do not properly interact with the GPU memory behavior of a certain driver for Intel integrated GPUs, which allows remote attackers to bypass the Same Origin Policy and read image data via vectors related to WebGL textures.

Mozilla Firefox 7.0 and Thunderbird 7.0, when the Direct2D (aka D2D) API is used on Windows in conjunction with the Azure graphics back-end, allow remote attackers to bypass the Same Origin Policy, and obtain sensitive image data from a different domain, by inserting this data into a canvas. NOTE: this issue exists because of a CVE-2011-2986 regression.