Firefox's HTML parser did not correctly interpret HTML comment tags, resulting in an incongruity with other browsers. This could have been used to escape HTML comments on pages that put user-controlled data in them. This vulnerability affects Firefox < 101.

By injecting a cookie with certain special characters, an attacker on a shared subdomain which is not a secure context could set and thus overwrite cookies from a secure context, leading to session fixation and other attacks. This vulnerability affects Firefox ESR < 102.3, Thunderbird < 102.3, and Firefox < 105.

An attacker could have abused XSLT error handling to associate attacker-controlled content with another origin which was displayed in the address bar. This could have been used to fool the user into submitting data intended for the spoofed origin. This vulnerability affects Thunderbird < 102.2, Thunderbird < 91.13, Firefox ESR < 91.13, Firefox ESR < 102.2, and Firefox < 104.

If upgrade-insecure-requests was specified in the Content Security Policy, and a link was dragged and dropped from that page, the link was not upgraded to https. This vulnerability affects Firefox < 70.

A "data:" URL loaded in a new tab did not inherit the Content Security Policy (CSP) of the original page, allowing for bypasses of the policy including the execution of JavaScript. In prior versions when "data:" documents also inherited the context of the original page this would allow for potential cross-site scripting (XSS) attacks. This vulnerability affects Firefox < 57.

When a malicious application installed on the user's device broadcast an Intent to Firefox for Android, arbitrary headers could have been specified, leading to attacks such as abusing ambient authority or session fixation. This was resolved by only allowing certain safe-listed headers. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 84.

JavaScript can be injected into an exported bookmarks file by placing JavaScript code into user-supplied tags in saved bookmarks. If the resulting exported HTML file is later opened in a browser this JavaScript will be executed. This could be used in social engineering and self-cross-site-scripting (self-XSS) attacks if users were convinced to add malicious tags to bookmarks, export them, and then open the resulting file. This vulnerability affects Firefox < 57.

Control characters prepended before "javascript:" URLs pasted in the addressbar can cause the leading characters to be ignored and the pasted JavaScript to be executed instead of being blocked. This could be used in social engineering and self-cross-site-scripting (self-XSS) attacks where users are convinced to copy and paste text into the addressbar. This vulnerability affects Firefox < 57.

A mechanism where when a new tab is loaded through JavaScript events, if fullscreen mode is then entered, the addressbar will not be rendered. This would allow a malicious site to displayed a spoofed addressbar, showing the location of an arbitrary website instead of the one loaded. Note: this issue only affects Firefox for Android. Desktop Firefox is unaffected. This vulnerability affects Firefox < 54.

The content security policy (CSP) "sandbox" directive did not create a unique origin for the document, causing it to behave as if the "allow-same-origin" keyword were always specified. This could allow a Cross-Site Scripting (XSS) attack to be launched from unsafe content. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.

A mechanism to inject static HTML into the RSS reader preview page due to a failure to escape characters sent as URL parameters for a feed's "TITLE" element. This vulnerability allows for spoofing but no scripted content can be run. This vulnerability affects Firefox < 53.

If a page is loaded from an original site through a hyperlink and contains a redirect to a "data:text/html" URL, triggering a reload will run the reloaded "data:text/html" page with its origin set incorrectly. This allows for a cross-site scripting (XSS) attack. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.

Malicious sites can display a spoofed addressbar on a page when the existing location bar on the new page is scrolled out of view if an HTML editable page element is user selected. Note: This attack only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 53.

When a "javascript:" URL is drag and dropped by a user into the addressbar, the URL will be processed and executed. This allows for users to be socially engineered to execute an XSS attack on themselves. This vulnerability affects Firefox < 53.

Malicious sites can display a spoofed location bar on a subsequently loaded page when the existing location bar on the new page is scrolled out of view if navigations between pages can be timed correctly. Note: This issue only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 51.

A mechanism to spoof the addressbar through the user interaction on the addressbar and the "onblur" event. The event could be used by script to affect text display to make the loaded site appear to be different from the one actually loaded within the addressbar. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.

A "javascript:" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52.

The "mozAddonManager" allows for the installation of extensions from the CDN for addons.mozilla.org, a publicly accessible site. This could allow malicious extensions to install additional extensions from the CDN in combination with an XSS attack on Mozilla AMO sites. This vulnerability affects Firefox < 51.

When browsing private tabs, some data related to location history or webpage thumbnails could be persisted incorrectly within the sandboxed app bundle after app termination This vulnerability affects Firefox for iOS < 127.

An OpenPGP digital signature includes information about the date when the signature was created. When displaying an email that contains a digital signature, the email's date will be shown. If the dates were different, then Thunderbird didn't report the email as having an invalid signature. If an attacker performed a replay attack, in which an old email with old contents are resent at a later time, it could lead the victim to believe that the statements in the email are current. Fixed versions of Thunderbird will require that the signature's date roughly matches the displayed date of the email. This vulnerability affects Thunderbird < 102 and Thunderbird < 91.11.

Spoofing issue in the Toolbar component in Firefox for Android. This vulnerability was fixed in Firefox 151.

Due to an error while parsing page content, it is possible for properly sanitized user input to be misinterpreted and lead to XSS hazards on web sites in certain circumstances. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

Spoofing issue in the Form Autofill component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

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.

Cross-site scripting (XSS) vulnerability in the dependency graphs in Bugzilla 2.16rc1 through 4.4.11, and 4.5.1 through 5.0.2 allows remote attackers to inject arbitrary web script or HTML.

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 47.0 allows remote attackers to bypass the Same Origin Policy and modify the location.host property via an invalid data: URL.

Mozilla Firefox before 47.0 ignores Content Security Policy (CSP) directives for cross-domain Java applets, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via a crafted applet.

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.

The WebExtension sandbox feature in browser/components/extensions/ext-tabs.js in Mozilla Firefox before 46.0 does not properly restrict principal inheritance during chrome.tabs.create and chrome.tabs.update API calls, which allows remote attackers to conduct Universal XSS (UXSS) attacks via a crafted extension that accesses a (1) javascript: or (2) data: URL.

Mozilla Firefox before 46.0 allows remote attackers to bypass the Content Security Policy (CSP) protection mechanism via the multipart/x-mixed-replace content type.

Mozilla Firefox before 47.0 allows remote attackers to spoof permission notifications via a crafted web site that rapidly triggers permission requests, as demonstrated by the microphone permission or the geolocation permission.

The Firefox Health Reports (aka FHR or about:healthreport) feature in Mozilla Firefox before 46.0 does not properly restrict the origin of events, which makes it easier for remote attackers to modify sharing preferences by leveraging access to the remote-report IFRAME element.

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 47.0 and Firefox ESR 45.x before 45.2 allow remote attackers to spoof the address bar via a SELECT element with a persistent menu.

Remote Agent, used in WebDriver, did not validate the Host or Origin headers. This could have allowed websites to connect back locally to the user's browser to control it. <br>*This bug only affected Firefox when WebDriver was enabled, which is not the default configuration.*. This vulnerability affects Firefox < 97.

Mozilla Firefox before 44.0 allows user-assisted remote attackers to spoof a trailing substring in the address bar by leveraging a user's paste of a (1) wyciwyg: URI or (2) resource: URI.

CRLF injection vulnerability in Mozilla Firefox 4.x through 10.0, Firefox ESR 10.x before 10.0.3, Thunderbird 5.0 through 10.0, Thunderbird ESR 10.x before 10.0.3, and SeaMonkey before 2.8 allows remote web servers to bypass intended Content Security Policy (CSP) restrictions and possibly conduct cross-site scripting (XSS) attacks via crafted HTTP headers.

The file-download dialog in Mozilla Firefox before 44.0 on OS X enables a certain button too quickly, which allows remote attackers to conduct clickjacking attacks via a crafted web site that triggers a single-click action in a situation where a double-click action was intended.

Mozilla Firefox 43.x mishandles attempts to connect to the Application Reputation service, which makes it easier for remote attackers to trigger an unintended download by leveraging the absence of reputation data.

Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7 mishandle a navigation sequence that returns to the original page, which allows remote attackers to spoof the address bar via vectors involving the history.back method and the location.protocol property.

The protocol-handler dialog in Mozilla Firefox before 44.0 allows remote attackers to conduct clickjacking attacks via a crafted web site that triggers a single-click action in a situation where a double-click action was intended.

browser/base/content/browser.js in Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7 allows remote attackers to spoof the address bar via a javascript: URL.

If a user installed an extension of a particular type, the extension could have auto-updated itself and while doing so, bypass the prompt which grants the new version the new requested permissions. This vulnerability affects Firefox < 97, Thunderbird < 91.6, and Firefox ESR < 91.6.

Focus was incorrectly allowing internal links to utilize the app scheme used for deeplinking, which could result in links potentially circumventing some URL safety checks This vulnerability affects Focus for iOS < 132.

Mozilla Firefox before 44.0 on Android does not ensure that HTTPS is used for a lightweight-theme installation, which allows man-in-the-middle attackers to replace a theme's images and colors by modifying the client-server data stream.

Mozilla Firefox before 44.0 on Android allows remote attackers to spoof the address bar via the scrollTo method.

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.

When the address bar was hidden due to scrolling on Android, a malicious page could create a fake address bar to fool the user in response to a visibilitychange event. This vulnerability was fixed in Firefox 144.

When styling and rendering an oversized `<select>` element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface. This vulnerability affects Firefox < 89.