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.

The startDocumentLoad function in browser/base/content/browser.js in Mozilla Firefox 3.5.x before 3.5.11 and 3.6.x before 3.6.7, and SeaMonkey before 2.0.6, does not properly implement the Same Origin Policy in certain circumstances related to the about:blank document and a document that is currently loading, which allows (1) remote web servers to conduct spoofing attacks via vectors involving a 204 (aka No Content) status code, and allows (2) remote attackers to conduct spoofing attacks via vectors involving a window.stop call.

Mozilla Firefox before 3.0.12 does not always use XPCCrossOriginWrapper when required during object construction, which allows remote attackers to bypass the Same Origin Policy and conduct cross-site scripting (XSS) attacks via a crafted document, related to a "cross origin wrapper bypass."

A compromised sandboxed content process can perform a Universal Cross-site Scripting (UXSS) attack on content from any site it can cause to be loaded in the same process. Because addons.mozilla.org and accounts.firefox.com have close ties to the Firefox product, malicious manipulation of these sites within the browser can potentially be used to modify a user's Firefox configuration. These two sites will now be isolated into their own process and not allowed to be loaded in a standard content process. This vulnerability affects Firefox < 69.

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.

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.

Cross-site scripting (XSS) vulnerability in the MozSearch plugin implementation in Mozilla Firefox before 3.0.9 allows user-assisted remote attackers to inject arbitrary web script or HTML via a javascript: URI in the SearchForm element.

Mozilla Firefox 3.0.x before 3.0.18 and 3.5.x before 3.5.8, and SeaMonkey before 2.0.3, does not properly support the application/octet-stream content type as a protection mechanism against execution of web script in certain circumstances involving SVG and the EMBED element, which allows remote attackers to bypass the Same Origin Policy and conduct cross-site scripting (XSS) attacks via an embedded SVG document.

Mozilla Firefox before 3.0.9, Thunderbird, and SeaMonkey do not properly implement the Same Origin Policy for (1) XMLHttpRequest, involving a mismatch for a document's principal, and (2) XPCNativeWrapper.toString, involving an incorrect __proto__ scope, which allows remote attackers to conduct cross-site scripting (XSS) attacks and possibly other attacks via a crafted document.

The jar: URI implementation in Mozilla Firefox before 3.0.9, Thunderbird, and SeaMonkey does not follow the Content-Disposition header of the inner URI, which allows remote attackers to conduct cross-site scripting (XSS) attacks and possibly other attacks via an uploaded .jar file with a "Content-Disposition: attachment" designation.

Mozilla Firefox before 3.0.9 and SeaMonkey 1.1.17 do not block javascript: URIs in Refresh headers in HTTP responses, which allows remote attackers to conduct cross-site scripting (XSS) attacks via vectors related to (1) injecting a Refresh header or (2) specifying the content of a Refresh header. NOTE: it was later reported that Firefox 3.6 a1 pre and Mozilla 1.7.x and earlier are also affected.

The Public Key Pinning (PKP) implementation in Mozilla Firefox before 33.0 does not properly consider the connection-coalescing behavior of SPDY and HTTP/2 in the case of a shared IP address, which allows man-in-the-middle attackers to bypass an intended pinning configuration and spoof a web site by providing a valid certificate from an arbitrary recognized Certification Authority.

Cross-site scripting vulnerability in Address Book of Cybozu Office 10.0.0 to 10.8.4 allows remote attackers to inject an arbitrary script via unspecified vectors. Note that this vulnerability occurs only when using Mozilla Firefox.

Mozilla Firefox 3.0.13 and earlier, 3.5, 3.6 a1 pre, and 3.7 a1 pre does not properly block data: URIs in Location headers in HTTP responses, which allows remote attackers to conduct cross-site scripting (XSS) attacks via vectors related to (1) injecting a Location header that contains JavaScript sequences in a data:text/html URI or (2) entering a data:text/html URI with JavaScript sequences when specifying the content of a Location header. NOTE: the JavaScript executes outside of the context of the HTTP site.

The Public Key Pinning (PKP) implementation in Mozilla Firefox before 33.0 skips pinning checks upon an unspecified issuer-verification error, which makes it easier for remote attackers to bypass an intended pinning configuration and spoof a web site via a crafted certificate that leads to presentation of the Untrusted Connection dialog to the user.

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.

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.

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.

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.

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.

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.

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.

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.

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.

When invoking protocol handlers for external protocols, a supplied parameter URL containing spaces was not properly escaped. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

WebExtensions with the correct permissions were able to create and install ServiceWorkers for third-party websites that would not have been uninstalled with the extension. This vulnerability affects Firefox < 95.