When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing. This vulnerability affects Firefox < 94.

Documents loaded with the CSP sandbox directive could have escaped the sandbox's script restriction by embedding additional content. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.

Mozilla Firefox before 2.0.0.8 and SeaMonkey before 1.1.5 can hide the window's titlebar when displaying XUL markup language documents, which makes it easier for remote attackers to conduct phishing and spoofing attacks by setting the hidechrome attribute.

By displaying a form validity message in the correct location at the same time as a permission prompt (such as for geolocation), the validity message could have obscured the prompt, resulting in the user potentially being tricked into granting the permission. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Through use of reportValidity() and window.open(), a plain-text validation message could have been overlaid on another origin, leading to possible user confusion and spoofing attacks. This vulnerability affects Firefox < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.

Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning to the user. This could lead to spoofing attacks on the browser UI including phishing. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

When delegating navigations to the operating system, Firefox would accept the `mk` scheme which might allow attackers to launch pages and execute scripts in Internet Explorer in unprivileged mode. *This bug only affects Firefox for Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 92, Thunderbird < 91.1, Thunderbird < 78.14, Firefox ESR < 78.14, and Firefox ESR < 91.1.

Due to an unusual sequence of attacker-controlled events, a Javascript alert() dialog with arbitrary (although unstyled) contents could be displayed over top an uncontrolled webpage of the attacker's choosing. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

The Reader View implementation in Mozilla Firefox before 42.0 has an improper whitelist, which makes it easier for remote attackers to bypass the Content Security Policy (CSP) protection mechanism and conduct cross-site scripting (XSS) attacks via vectors involving SVG animations and the about:reader URL.

Mozilla Firefox before 41.0 on Android allows user-assisted remote attackers to spoof address-bar attributes by leveraging lack of navigation after a paste of a URL with a nonstandard scheme, as demonstrated by spoofing an SSL attribute.

Cross-site scripting (XSS) vulnerability in the quips feature in Mozilla Bugzilla 2.10 through 2.17 allows remote attackers to inject arbitrary web script or HTML via the "show all quips" page.

The nsCSPHostSrc::permits function in dom/security/nsCSPUtils.cpp in Mozilla Firefox before 40.0 does not implement the Content Security Policy Level 2 exceptions for the blob, data, and filesystem URL schemes during wildcard source-expression matching, which might make it easier for remote attackers to conduct cross-site scripting (XSS) attacks by leveraging unexpected policy-enforcement behavior.

By using the reflected URL in some special resource URIs, such as chrome:, it is possible to inject stylesheets and bypass Content Security Policy (CSP). This vulnerability affects Firefox < 63.

When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. This vulnerability affects Firefox < 63.

js/src/proxy/Proxy.cpp in Mozilla Firefox before 41.0 mishandles certain receiver arguments, which allows remote attackers to bypass intended window access restrictions via a crafted web site.

Cross-site scripting (XSS) vulnerability in the FTP view feature in Mozilla 1.0 allows remote attackers to inject arbitrary web script or HTML via the title tag of an ftp URL.

The TLS protocol 1.2 and earlier, when a DHE_EXPORT ciphersuite is enabled on a server but not on a client, does not properly convey a DHE_EXPORT choice, which allows man-in-the-middle attackers to conduct cipher-downgrade attacks by rewriting a ClientHello with DHE replaced by DHE_EXPORT and then rewriting a ServerHello with DHE_EXPORT replaced by DHE, aka the "Logjam" issue.

The Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin with unencrypted connections on port 80. However, if a second encrypted port on the same IP address (e.g. port 8443) did not opt-in to opportunistic encryption; a network attacker could forward a connection from the browser to port 443 to port 8443, causing the browser to treat the content of port 8443 as same-origin with HTTP. This was resolved by disabling the Opportunistic Encryption feature, which had low usage. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Mozilla Network Security Services (NSS) before 3.19.1, as used in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, and other products, does not properly perform Elliptical Curve Cryptography (ECC) multiplications, which makes it easier for remote attackers to spoof ECDSA signatures via unspecified vectors.

A malicious website that causes an HTTP Authentication dialog to be spawned could trick the built-in password manager to suggest passwords for the currently active website instead of the website that triggered the dialog. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 89.

Multiple cross-site scripting (XSS) vulnerabilities in the Search app in Gaia in Mozilla Firefox OS before 2.2 allow remote attackers to inject arbitrary HTML via the (1) name or (2) title field in card content associated with a search link that is mishandled after a HOME button press or a Show Windows action, as demonstrated by embedding an arbitrary application or spoofing the account-creation page.

Firefox for Android could get stuck in fullscreen mode and not exit it even after normal interactions that should cause it to exit. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 91.

Mozilla Firefox before 39.0, Firefox ESR 38.x before 38.1, and Thunderbird before 38.1 do not enforce key pinning upon encountering an X.509 certificate problem that generates a user dialog, which allows user-assisted man-in-the-middle attackers to bypass intended access restrictions by triggering a (1) expired certificate or (2) mismatched hostname for a domain with pinning enabled.

Lack of escaping allowed HTML injection when a webpage was viewed in Reader View. While a Content Security Policy prevents direct code execution, HTML injection is still possible. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 88.

If a MIME encoded email contains an OpenPGP inline signed or encrypted message part, but also contains an additional unprotected part, Thunderbird did not indicate that only parts of the message are protected. This vulnerability affects Thunderbird < 78.10.2.

Cross-site scripting (XSS) vulnerability in the Search app in Gaia in Mozilla Firefox OS before 2.2 allows remote attackers to inject arbitrary HTML via a crafted search link that is mishandled after re-opening the browser or opening the tab view.

Mozilla Network Security Services (NSS) before 3.19, as used in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, Thunderbird before 38.1, and other products, does not properly determine state transitions for the TLS state machine, which allows man-in-the-middle attackers to defeat cryptographic protection mechanisms by blocking messages, as demonstrated by removing a forward-secrecy property by blocking a ServerKeyExchange message, aka a "SMACK SKIP-TLS" issue.

Address bar search suggestions in private browsing mode were re-using session data from normal mode. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 89.

Mozilla Firefox before 2.0.0.10 and SeaMonkey before 1.1.7 sets the Referer header to the window or frame in which script is running, instead of the address of the content that initiated the script, which allows remote attackers to spoof HTTP Referer headers and bypass Referer-based CSRF protection schemes by setting window.location and using a modal alert dialog that causes the wrong Referer to be sent.

Through a series of DOM manipulations, a message, over which the attacker had control of the text but not HTML or formatting, could be overlaid on top of another domain (with the new domain correctly shown in the address bar) resulting in possible user confusion. This vulnerability affects Firefox < 90.

Hubs Cloud allows users to download shared content, specifically HTML and JS, which could allow javascript execution in the Hub Cloud instance’s primary hosting domain.*. This vulnerability affects Hubs Cloud < mozillareality/reticulum/1.0.1/20210618012634.

When a user has already allowed a website to access microphone and camera, disabling camera sharing would not fully prevent the website from re-enabling it without an additional prompt. This was only possible if the website kept recording with the microphone until re-enabling the camera. This vulnerability affects Firefox < 89.

The UITour::onPageEvent function in Mozilla Firefox before 36.0 does not ensure that an API call originates from a foreground tab, which allows remote attackers to conduct spoofing and clickjacking attacks by leveraging access to a UI Tour web site.

Mozilla Firefox before 37.0 on OS X does not ensure that the cursor is visible, which allows remote attackers to conduct clickjacking attacks via a Flash object in conjunction with DIV elements associated with layered presentation, and crafted JavaScript code that interacts with an IMG element.

The HTTP Alternative Services feature in Mozilla Firefox before 37.0.1 allows man-in-the-middle attackers to bypass an intended X.509 certificate-verification step for an SSL server by specifying that server in the uri-host field of an Alt-Svc HTTP/2 response header.

Mozilla Firefox before 37.0 does not require an HTTPS session for lightweight theme add-on installations, which allows man-in-the-middle attackers to bypass an intended user-confirmation requirement by deploying a crafted web site and conducting a DNS spoofing attack against a mozilla.org subdomain.

Cross-site scripting (XSS) vulnerability in the Admin Control Center in Sentinel HASP Run-time Environment 5.95 and earlier in SafeNet Sentinel HASP (formerly Aladdin HASP SRM) run-time installer before 6.x and SDK before 5.11, as used in 7 Technologies (7T) IGSS 7 and other products, when Firefox 2.0 is used, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors that trigger write access to a configuration file.

The DOMParser API did not properly process '<noscript>' elements for escaping. This could be used as an mXSS vector to bypass an HTML Sanitizer. This vulnerability affects Firefox < 86.

When sharing geolocation during an active WebRTC share, Firefox could have reset the webRTC sharing state in the user interface, leading to loss of control over the currently granted permission. This vulnerability affects Firefox < 85.

The browser could have been confused into transferring a pointer lock state into another tab, which could have lead to clickjacking attacks. This vulnerability affects Firefox < 85.

Through complicated navigations with new windows, an HTTP page could have inherited a secure lock icon from an HTTPS page. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

By utilizing 3D CSS in conjunction with Javascript, content could have been rendered outside the webpage's viewport, resulting in a spoofing attack that could have been used for phishing or other attacks on a user. This vulnerability affects Firefox < 88.

An XSS bug in internal error pages could have led to various spoofing attacks, including other error pages and the address bar. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 85.

Using techniques that built on the slipstream research, a malicious webpage could have scanned both an internal network's hosts as well as services running on the user's local machine utilizing WebRTC connections. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Navigations through the Android-specific `intent` URL scheme could have been misused to escape iframe sandbox. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 85.

The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers. This vulnerability affects Firefox < 86.

A vulnerability where a WebExtension can run content scripts in disallowed contexts following navigation or other events. This allows for potential privilege escalation by the WebExtension on sites where content scripts should not be run. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.

The cert_TestHostName function in lib/certdb/certdb.c in the certificate-checking implementation in Mozilla Network Security Services (NSS) before 3.16 accepts a wildcard character that is embedded in an internationalized domain name's U-label, which might allow man-in-the-middle attackers to spoof SSL servers via a crafted certificate.

The docshell implementation in Mozilla Firefox before 29.0, Firefox ESR 24.x before 24.5, Thunderbird before 24.5, and SeaMonkey before 2.26 allows remote attackers to trigger the loading of a URL with a spoofed baseURI property, and conduct cross-site scripting (XSS) attacks, via a crafted web site that performs history navigation.