When receiving an HTML email that specified to load an <code>iframe</code> element from a remote location, a request to the remote document was sent. However, Thunderbird didn't display the document. This vulnerability affects Thunderbird < 102.2.1 and Thunderbird < 91.13.1.

The file-download implementation in Mozilla Firefox before 27.0 and SeaMonkey before 2.24 does not properly restrict the timing of button selections, which allows remote attackers to conduct clickjacking attacks, and trigger unintended launching of a downloaded file, via a crafted web site.

Mozilla Firefox before 26.0 and SeaMonkey before 2.23 do not properly consider the sandbox attribute of an IFRAME element during processing of a contained OBJECT element, which allows remote attackers to bypass intended sandbox restrictions via a crafted web site.

It was possible to recreate previous cursor spoofing attacks against users with a zoomed native cursor. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

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.

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.

It was possible for certain browser prompts and dialogs to be activated or dismissed unintentionally by the user due to an insufficient activation-delay. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

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.

Cross-origin iframes that contained a login form could have been recognized by the login autofill service, and populated. This could have been used in clickjacking attacks, as well as be read across partitions in dynamic first party isolation. This vulnerability affects Firefox < 83.

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.

Using object or embed tags, it was possible to frame other websites, even if they disallowed framing using the X-Frame-Options header. This vulnerability affects Thunderbird < 78 and Firefox < 78.0.2.

The z-order of the browser windows could be manipulated to hide the fullscreen notification. This could potentially be leveraged to perform a spoofing attack. This vulnerability was fixed in Firefox 135 and Thunderbird 135.

Multiple prompts and panels from both Firefox and the Android OS could be used to obscure the notification announcing the transition to fullscreen mode after the fix for CVE-2023-6870 in Firefox 121. This could lead to spoofing the browser UI if the sudden appearance of the prompt distracted the user from noticing the visual transition happening behind the prompt. These notifications now use the Android Toast feature. *This bug only affects Firefox on Android. Other operating systems are unaffected.* This vulnerability affects Firefox < 130.

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 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.

The fullscreen notification could have been hidden on Firefox for Android by using download popups, resulting in potential user confusion or spoofing attacks. <br>*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 111.

By displaying a prompt with a long description, the fullscreen notification could have been hidden, resulting in potential user confusion or spoofing attacks. <br>*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 111.

The exception page for the HTTPS-Only feature, displayed when a website is opened via HTTP, lacked an anti-clickjacking delay, potentially allowing an attacker to trick a user into granting an exception and loading a webpage over HTTP. This vulnerability was fixed in Firefox 140 and Thunderbird 140.

When "%2F" was present in a manifest URL, Firefox's AppCache behavior may have become confused and allowed a manifest to be served from a subdirectory. This could cause the appcache to be used to service requests for the top level directory. This vulnerability affects Firefox < 78.

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.

The "Forget about this site" feature in the History pane is intended to remove all saved user data that indicates a user has visited a site. This includes removing any HTTP Strict Transport Security (HSTS) settings received from sites that use it. Due to a bug, sites on the pre-load list also have their HSTS setting removed. On the next visit to that site if the user specifies an http: URL rather than secure https: they will not be protected by the pre-loaded HSTS setting. After that visit the site's HSTS setting will be restored. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.

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.

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.

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. *Note: Spectre mitigations are currently enabled for all users by default settings.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

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.

When arbitrary text is sent over an FTP connection and a page reload is initiated, it is possible to create a modal alert message with this text as the content. This could potentially be used for social engineering attacks. This vulnerability affects Firefox < 66.

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.

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.

If array shift operations are not used, the Garbage Collector may have become confused about valid objects. This vulnerability affects Firefox < 101.

If there was a PAC URL set and the server that hosts the PAC was not reachable, OCSP requests would have been blocked, resulting in incorrect error pages being shown. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.

A website could have obscured the fullscreen notification by using a dropdown select input element. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.

GUI overlay vulnerability in Mozilla Firefox before 2.0.0.13 and SeaMonkey before 1.1.9 allows remote attackers to spoof form elements and redirect user inputs via a borderless XUL pop-up window from a background tab.

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.

When a URL was provided in a link querystring parameter, Firefox for Android would follow that URL instead of the correct URL, potentially leading to phishing attacks. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox 140.

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.

Cross-site scripting (XSS) vulnerability in Mozilla Thunderbird 17.x through 17.0.8, Thunderbird ESR 17.x through 17.0.10, and SeaMonkey before 2.20 allows user-assisted remote attackers to inject arbitrary web script or HTML via an e-mail message containing a data: URL in a (1) OBJECT or (2) EMBED element, a related issue to CVE-2013-6674.

Bugzilla 2.x through 4.0.x before 4.0.15, 4.1.x and 4.2.x before 4.2.11, 4.3.x and 4.4.x before 4.4.6, and 4.5.x before 4.5.6 does not ensure that a scalar context is used for certain CGI parameters, which allows remote attackers to conduct cross-site scripting (XSS) attacks by sending three values for a single parameter name.

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.

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.

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 resizing a popup after requesting fullscreen access, the popup would not display the fullscreen notification. This vulnerability affects Firefox < 98, Firefox ESR < 91.7, and Thunderbird < 91.7.

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

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.

Cross-site scripting (XSS) vulnerability in the Space function in Cybozu Garoon before 3.7.0, when Firefox is used, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

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.

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.

Cross-site scripting (XSS) vulnerability in clickstream.js in Y! Toolbar plugin for FireFox 3.1.0.20130813024103 for Mac, and 2.5.9.2013418100420 for Windows, allows remote attackers to inject arbitrary web script or HTML via a crafted URL that is stored by the victim.

Cross-site scripting (XSS) vulnerability in Mozilla Thunderbird 17.x through 17.0.8, Thunderbird ESR 17.x through 17.0.10, and SeaMonkey before 2.20 allows user-assisted remote attackers to inject arbitrary web script or HTML via an e-mail message containing a data: URL in an IFRAME element, a related issue to CVE-2014-2018.