Websites directing users to long URLs that caused eliding to occur in the location view could leverage the truncating behavior to potentially trick users into thinking they were on a different webpage. This vulnerability was fixed in Focus 138.

Under certain conditions, an attacker with the ability to redirect users to a malicious site via an open redirect on a trusted site, may be able to spoof the address bar contents. This can lead to a malicious site to appear to have the same URL as the trusted site. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox for Android < 130.0.1.

If a site had been granted the permission to open popup windows, it could cause Select elements to appear on top of another site to perform a spoofing attack. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, and Thunderbird < 128.2.

Requests initiated through reader mode did not properly omit cookies with a SameSite attribute. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

When closed or sent to the background, Firefox for Android would not properly record and persist HSTS settings.<br>*Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 100.

open redirect in pollbot (pollbot.services.mozilla.com) in versions before 1.4.6

The 'Copy Image Link' context menu action would copy the final image URL after redirects. By embedding an image that triggered authentication flows - in conjunction with a Content Security Policy that stopped a redirection chain in the middle - the final image URL could be one that contained an authentication token used to takeover a user account. If a website tricked a user into copy and pasting the image link back to the page, the page would be able to steal the authentication tokens. This was fixed by making the action return the original URL, before any redirects. This vulnerability affects Firefox < 94.

When a user scans a QR Code with the QR Code Scanner feature, the user is not prompted before being navigated to the page specified in the code. This may surprise the user and potentially direct them to unwanted content. This vulnerability affects Firefox for iOS < 129.

An attacker could have performed HTML template injection via Reader Mode and exfiltrated user information. This vulnerability affects Firefox for iOS < 120.

An open redirect is present on the gateway's login page, which could cause a user to be redirected to a malicious site after logging in.

When using the Performance API, an attacker was able to notice subtle differences between PerformanceEntries and thus learn whether the target URL had been subject to a redirect. This vulnerability affects Firefox < 103.

When choosing a site-isolated process for a document loaded from a data: URL that was the result of a redirect, Firefox would load that document in the same process as the site that issued the redirect. This bypassed the site-isolation protections against Spectre-like attacks on sites that host an "open redirect". Firefox no longer follows HTTP redirects to data: URLs. This vulnerability affects Firefox < 114.

Using a redirect embedded into <code>sourceMappingUrls</code> could allow for navigation to external protocol links in sandboxed iframes without <code>allow-top-navigation-to-custom-protocols</code>. This vulnerability affects Firefox for Android < 112, Firefox < 112, and Focus for Android < 112.

By exploiting an Open Redirect vulnerability on a website, an attacker could have spoofed the site displayed in the download file dialog to show the original site (the one suffering from the open redirect) rather than the site the file was actually downloaded from. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Focus for iOS would not respect a Content-Disposition header of type Attachment and would incorrectly display the content inline, potentially allowing for XSS attacks. This vulnerability was fixed in Focus for iOS 142.

WebExtensions could use the "mozAddonManager" API by modifying the CSP headers on sites with the appropriate permissions and then using host requests to redirect script loads to a malicious site. This allows a malicious extension to then install additional extensions without explicit user permission. This vulnerability affects Firefox < 51.

Using the <code>S.browser_fallback_url parameter</code> parameter, an attacker could redirect a user to a URL and cause SameSite=Strict cookies to be sent.<br>*This issue only affects Firefox for Android. Other operating systems are not affected.*. This vulnerability affects Firefox < 107.

When a user typed a URL in the address bar or the search bar and quickly hit the enter key, a website could sometimes capture that event and then redirect the user before navigation occurred to the desired, entered address. To construct a convincing spoof the attacker would have had to guess what the user was typing, perhaps by suggesting it. This vulnerability affects Firefox < 84.

Even when an iframe was sandboxed with <code>allow-top-navigation-by-user-activation</code>, if it received a redirect header to an external protocol the browser would process the redirect and prompt the user as appropriate. This vulnerability affects Firefox < 102.

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.

Utilizing a 302 redirect, an attacker could have conducted a Universal Cross-Site Scripting (UXSS) on a victim website, if the victim had a link to the attacker's website. This vulnerability affects Focus for iOS < 123.

Mozilla Firefox before 31.0 and Thunderbird before 31.0 do not properly implement the sandbox attribute of the IFRAME element, which allows remote attackers to bypass intended restrictions on same-origin content via a crafted web site in conjunction with a redirect.

Using a markup injection an attacker could have stolen nonce values. This could have been used to bypass strict content security policies. This vulnerability affects Firefox < 124, Firefox ESR < 115.9, and Thunderbird < 115.9.

The permission prompt input delay could expire while the window is not in focus. This makes it vulnerable to clickjacking by malicious websites. This vulnerability affects Firefox < 124, Firefox ESR < 115.10, and Thunderbird < 115.10.

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.

An object tag with a data URI did not correctly inherit the document's Content Security Policy. This allowed a CSP bypass in a cross-origin frame if the document's policy explicitly allowed data: URIs. This vulnerability affects Firefox < 70.

The CERT_VerifyCert function in lib/certhigh/certvfy.c in Mozilla Network Security Services (NSS) 3.15 before 3.15.3 provides an unexpected return value for an incompatible key-usage certificate when the CERTVerifyLog argument is valid, which might allow remote attackers to bypass intended access restrictions via a crafted certificate.

In Nunjucks versions prior to version 3.2.4, it was possible to bypass the restrictions which are provided by the autoescape functionality. If there are two user-controlled parameters on the same line used in the views, it was possible to inject cross site scripting payloads using the backslash \ character.

Mitigation bypass in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 145, Firefox ESR 140.5, Firefox ESR 115.30, Thunderbird 145, and Thunderbird 140.5.

Set-Cookie response headers were being incorrectly honored in multipart HTTP responses. If an attacker could control the Content-Type response header, as well as control part of the response body, they could inject Set-Cookie response headers that would have been honored by the browser. This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.

Some unicode characters are incorrectly treated as whitespace during the parsing of web content instead of triggering parsing errors. This allows malicious code to then be processed, evading cross-site scripting (XSS) filtering. This vulnerability affects Firefox < 68.

Mozilla Firefox before 1.5.0.5, Thunderbird before 1.5.0.5, and SeaMonkey before 1.0.3 allows remote attackers to hijack native DOM methods from objects in another domain and conduct cross-site scripting (XSS) attacks using DOM methods of the top-level object.

Failure to correctly handle null bytes when processing HTML entities resulted in Firefox incorrectly parsing these entities. This could have led to HTML comment text being treated as HTML which could have led to XSS in a web application under certain conditions. It could have also led to HTML entities being masked from filters - enabling the use of entities to mask the actual characters of interest from filters. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability was fixed in Firefox 144, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.

Application permissions give additional remote troubleshooting permission to the site input.mozilla.org, which has been retired and now redirects to another site. This additional permission is unnecessary and is a potential vector for malicious attacks. This vulnerability affects Firefox < 68.

By using a form with a data URI it was possible to gain access to the privileged JSONView object that had been cloned into content. Impact from exposing this object appears to be minimal, however it was a bypass of existing defense in depth mechanisms. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

If two same-origin documents set document.domain differently to become cross-origin, it was possible for them to call arbitrary DOM methods/getters/setters on the now-cross-origin window. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

A missing delay in directory upload UI could have made it possible for an attacker to trick a user into granting permission via clickjacking. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Thunderbird < 128.3, and Thunderbird < 131.

Firefox adds web-compatibility shims in place of some tracking scripts blocked by Enhanced Tracking Protection. On a site protected by Content Security Policy in "strict-dynamic" mode, an attacker able to inject an HTML element could have used a DOM Clobbering attack on some of the shims and achieved XSS, bypassing the CSP strict-dynamic protection. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, and Firefox ESR < 128.1.

A vulnerability in register allocation in JavaScript can lead to type confusion, allowing for an arbitrary read and write. This leads to remote code execution inside the sandboxed content process when triggered. This vulnerability affects Firefox ESR < 60.2.2 and Firefox < 62.0.3.

Offscreen Canvas did not properly track cross-origin tainting, which could be used to access image data from another site in violation of same-origin policy. This vulnerability affects Firefox < 127, Firefox ESR < 115.12, and Thunderbird < 115.12.

When injecting an HTML base element, some requests would ignore the CSP's base-uri settings and accept the injected element's base instead. This vulnerability affects Firefox ESR < 102.3, Thunderbird < 102.3, and Firefox < 105.

By manipulating the fullscreen feature while opening a data-list, an attacker could have overlaid a text box over the address bar. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 127.

An improper implementation of the new iframe sandbox keyword <code>allow-top-navigation-by-user-activation</code> could lead to script execution without <code>allow-scripts</code> being present. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

The ssl_Do1stHandshake function in sslsecur.c in libssl in Mozilla Network Security Services (NSS) before 3.15.4, when the TLS False Start feature is enabled, allows man-in-the-middle attackers to spoof SSL servers by using an arbitrary X.509 certificate during certain handshake traffic.

Mozilla Firefox before 20.0 and SeaMonkey before 2.17 do not prevent origin spoofing of tab-modal dialogs, which allows remote attackers to conduct phishing attacks via a crafted web site.

A bug in popup notifications' interaction with WebAuthn made it easier for an attacker to trick a user into granting permissions. This vulnerability affects Firefox < 126, Firefox ESR < 115.11, and Thunderbird < 115.11.

When receiving a URL through a SEND intent, Firefox would have searched for the text, but subsequent usages of the address bar might have caused the URL to load unintentionally, which could lead to XSS and spoofing attacks. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 95.

Mozilla Firefox before 3.6 is vulnerable to XSS via the rendering of Cascading Style Sheets

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.