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.
When exiting fullscreen mode, an iframe could have confused the browser about the current state of fullscreen, resulting in potential user confusion or spoofing attacks. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.
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.
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.
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.
The parent process would not properly check whether the Speech Synthesis feature is enabled, when receiving instructions from a child process. This vulnerability affects Thunderbird < 91.9.
Internal URLs are protected by a secret UUID key, which could have been leaked to web page through the Referrer header. This vulnerability affects Firefox for iOS < 102.
Cross-site scripting (XSS) vulnerability in Mozilla Firefox before 3.0.9, Thunderbird, and SeaMonkey allows remote attackers to inject arbitrary web script or HTML via vectors involving XBL JavaScript bindings and remote stylesheets, as exploited in the wild by a March 2009 eBay listing.
A `<dialog>` element could have been manipulated to paint content outside of a sandboxed iframe. This could allow untrusted content to display under the guise of trusted content. This vulnerability affects Firefox < 121.
An attacker could have injected CSS into stylesheets accessible via internal URIs, such as resource:, and in doing so bypass a page's Content Security Policy. This vulnerability affects Firefox ESR < 91.11, Thunderbird < 102, Thunderbird < 91.11, and Firefox < 101.
Spoofing issue in the Address Bar component. This vulnerability affects Firefox < 142 and Firefox ESR < 140.2.
An attacker could have created a malicious link using bidirectional characters to spoof the location in the address bar when visited. This vulnerability affects Firefox < 117, Firefox ESR < 115.4, and Thunderbird < 115.4.1.
When reusing existing popups Firefox would have allowed them to cover the fullscreen notification UI, which could have enabled browser spoofing attacks. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
If an attacker needed a user to load an insecure http: page and knew that user had enabled HTTPS-only mode, the attacker could have tricked the user into clicking to grant an HTTPS-only exception if they could get the user to participate in a clicking game. This vulnerability affects Firefox < 120.
When in an endless loop, a website specifying a custom cursor using CSS could make it look like the user is interacting with the user interface, when they are not. This could lead to a perceived broken state, especially when interactions with existing browser dialogs and warnings do not work. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.
When a JavaScript URL (javascript:) is evaluated and the result is a string, this string is parsed to create an HTML document, which is then presented. Previously, this document's URL (as reported by the document.location property, for example) was the originating javascript: URL which could lead to spoofing attacks; it is now correctly the URL of the originating document. This vulnerability affects Firefox < 74.
After a website had entered fullscreen mode, it could have used a previously opened popup to obscure the notification that indicates the browser is in fullscreen mode. Combined with spoofing the browser chrome, this could have led to confusing the user about the current origin of the page and credential theft or other attacks. This vulnerability affects Firefox < 74.
In Mozilla Bleach before 3.12, a mutation XSS in bleach.clean when RCDATA and either svg or math tags are whitelisted and the keyword argument strip=False.
If a template tag was used in a select tag, the parser could be confused and allow JavaScript parsing and execution when it should not be allowed. A site that relied on the browser behaving correctly could suffer a cross-site scripting vulnerability as a result. In general, this flaw cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but is potentially a risk in browser or browser-like contexts. This vulnerability affects Thunderbird < 68.5, Firefox < 73, and Firefox < ESR68.5.
A reflected XSS vulnerability exists within the gateway, allowing an attacker to craft a specialized URL which could steal the user's authentication token. When combined with CVE-2020-6803, an attacker could fully compromise the system.
When following a link that opened an intent://-schemed URL, causing a custom tab to be opened, Firefox for Android could be tricked into displaying the incorrect URI. <br> *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.
The session restore feature in Mozilla Firefox 3.x before 3.0.4 and 2.x before 2.0.0.18 allows remote attackers to violate the same origin policy to conduct cross-site scripting (XSS) attacks and execute arbitrary JavaScript with chrome privileges via unknown vectors.
Firefox could have incorrectly parsed a URL and rewritten it to the youtube.com domain when parsing the URL specified in an `embed` tag. This could have bypassed website security checks that restricted which domains users were allowed to embed. This vulnerability affects Firefox < 140, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
When a link can be opened in an external application, Firefox for Android will, by default, prompt the user before doing so. An attacker could have bypassed this prompt, potentially exposing the user to security vulnerabilities or privacy leaks in external applications. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 140.
Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
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.
Multiple cross-site scripting (XSS) vulnerabilities in Mozilla Firefox before 2.0.0.12, Thunderbird before 2.0.0.12, and SeaMonkey before 1.1.8 allow remote attackers to inject arbitrary web script or HTML via certain character encodings, including (1) a backspace character that is treated as whitespace, (2) 0x80 with Shift_JIS encoding, and (3) "zero-length non-ASCII sequences" in certain Asian character sets.
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.
Mozilla Firefox 3.x before 3.0.5 and 2.x before 2.0.0.19, Thunderbird 2.x before 2.0.0.19, and SeaMonkey 1.x before 1.1.14 does not properly parse URLs with leading whitespace or control characters, which might allow remote attackers to misrepresent URLs and simplify phishing attacks.
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.
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.
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.
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.
Unspecified vulnerability in the session-restore feature in Mozilla Firefox 3.x before 3.0.5 and 2.x before 2.0.0.19 allows remote attackers to bypass the same origin policy, inject content into documents associated with other domains, and conduct cross-site scripting (XSS) attacks via unknown vectors related to restoration of SessionStore data.
Mozilla Firefox before 28.0 and SeaMonkey before 2.25 allow remote attackers to spoof the domain name in the WebRTC (1) camera or (2) microphone permission prompt by triggering navigation at a certain time during generation of this prompt.
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.
When browsing a document hosted on an IP address, an attacker could insert certain characters to flip domain and path information in the address bar. This vulnerability affects Firefox < 77.
Through a series of API calls and redirects, an attacker-controlled alert dialog could have been displayed on another website (with the victim website's URL shown). This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.
Malicious websites could have confused Firefox into showing the wrong origin when asking to launch a program and handling an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.
When a user downloaded a file in Firefox for Android, if a cookie is set, it would have been re-sent during a subsequent file download operation on the same domain, regardless of whether the original and subsequent request were in private and non-private browsing modes. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.
When a HTTPS pages was embedded in a HTTP page, and there was a service worker registered for the former, the service worker could have intercepted the request for the secure page despite the iframe not being a secure context due to the (insecure) framing. This vulnerability affects Firefox < 84.
In some cases, removing HTML elements during sanitization would keep existing SVG event handlers and therefore lead to XSS. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
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.
It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
OneCRL was non-functional in the new Firefox for Android due to a missing service initialization. This could result in a failure to enforce some certificate revocations. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.
A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even after sanitization. An attacker already capable of exploiting an XSS vulnerability in privileged internal pages could have used this attack to bypass our built-in sanitizer. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
When accepting a malicious intent from other installed apps, Firefox for Android accepted manifests from arbitrary file paths and allowed declaring webapp manifests for other origins. This could be used to gain fullscreen access for UI spoofing and could also lead to cross-origin attacks on targeted websites. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.
By attempting to connect a website using an unresponsive port, an attacker could have controlled the content of a tab while the URL bar displayed the original domain. *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 84.