A crafted URL using a blob: URI could have hidden the true origin of the page, resulting in a potential spoofing attack. *Note: This issue only affected Android operating systems. Other operating systems are unaffected.* This vulnerability affects Firefox < 141.

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.

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 affects Firefox < 140.

By confusing the browser, the fullscreen notification could have been delayed or suppressed, resulting in potential user confusion or spoofing attacks. This vulnerability affects Firefox < 108.

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.

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 affects Firefox < 140 and Thunderbird < 140.

The incorrect domain may have been displayed in the address bar during an interrupted navigation attempt. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 133 and Thunderbird < 133.

An attacker could cause a select dropdown to be shown over another tab; this could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 133, Firefox ESR < 128.5, Thunderbird < 133, and Thunderbird < 128.5.

A phishing site could have repurposed an `about:` dialog to show phishing content with an incorrect origin in the address bar. This vulnerability affects Firefox < 122 and Thunderbird < 115.7.

It was possible for certain browser prompts and dialogs to be activated or dismissed unintentionally by the user due to an incorrect timestamp used to prevent input after page load. This vulnerability affects Firefox < 122, Firefox ESR < 115.7, and Thunderbird < 115.7.

In some instances, the user-agent would allow push requests which lacked a valid VAPID even though the push manager subscription defined one. This could allow empty messages to be sent from unauthorized parties. *This bug only affects Firefox on Android.* This vulnerability affects Firefox < 121.

Under certain conditions, Firefox did not display a warning when a user attempted to navigate to a new protocol handler. This vulnerability affects Firefox < 121.

A malicious web site can enter fullscreen mode while simultaneously triggering a WebAuthn prompt. This could have obscured the fullscreen notification and could have been leveraged in a spoofing attack. This vulnerability affects Firefox < 119.

The signature of a digitally signed S/MIME email message may optionally specify the signature creation date and time. If present, Thunderbird did not compare the signature creation date with the message date and time, and displayed a valid signature despite a date or time mismatch. This could be used to give recipients the impression that a message was sent at a different date or time. This vulnerability affects Thunderbird < 115.6.

When processing a PGP/MIME payload that contains digitally signed text, the first paragraph of the text was never shown to the user. This is because the text was interpreted as a MIME message and the first paragraph was always treated as an email header section. A digitally signed text from a different context, such as a signed GIT commit, could be used to spoof an email message. This vulnerability affects Thunderbird < 115.6.

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.

When network partitioning was enabled, e.g. as a result of Enhanced Tracking Protection settings, a TLS error page would allow the user to override an error on a domain which had specified HTTP Strict Transport Security (which implies that the error should not be override-able.) This issue did not affect the network connections, and they were correctly upgraded to HTTPS automatically. This vulnerability affects Firefox < 90.

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.

When a user has already allowed a website to access microphone and camera, disabling camera sharing would not fully prevent the website from re-enabling it without an additional prompt. This was only possible if the website kept recording with the microphone until re-enabling the camera. This vulnerability affects Firefox < 89.

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.

If a MIME encoded email contains an OpenPGP inline signed or encrypted message part, but also contains an additional unprotected part, Thunderbird did not indicate that only parts of the message are protected. This vulnerability affects Thunderbird < 78.10.2.

Websites redirecting to a non-HTTP scheme URL could allow a website address to be spoofed for a malicious page This vulnerability affects Firefox for iOS < 136.

Scanning certain QR codes that included text with a website URL could allow the URL to be opened without presenting the user with a confirmation alert first This vulnerability affects Firefox for iOS < 136.

Opening Javascript links in a new tab via long-press in the Firefox iOS client could result in a malicious script spoofing the URL of the new tab. This vulnerability affects Firefox for iOS < 134.

When sharing geolocation during an active WebRTC share, Firefox could have reset the webRTC sharing state in the user interface, leading to loss of control over the currently granted permission. This vulnerability affects Firefox < 85.

Mozilla Firefox before 25 allows modification of anonymous content of pluginProblem.xml binding

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 affects Firefox < 135 and Thunderbird < 135.

A website that had permission to access the microphone could record audio without the audio notification being shown. This bug does not allow the attacker to bypass the permission prompt - it only affects the notification shown once permission has been granted.<br />*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 104.

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.

In multiple cases browser prompts could have been obscured by popups controlled by content. These could have led to potential user confusion and spoofing attacks. This vulnerability affects Firefox < 113, Firefox ESR < 102.11, and Thunderbird < 102.11.

The frame iterator could get stuck in a loop when encountering certain wasm frames leading to incorrect stack traces. This vulnerability affects Firefox < 128 and Thunderbird < 128.

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 compromised content process could have updated the document URI. This could have allowed an attacker to set an arbitrary URI in the address bar or history. This vulnerability affects Firefox < 122.

Applications which spawn a Toast notification in a background thread may have obscured fullscreen notifications displayed by Firefox. *This issue only affects Android versions of Firefox and Firefox Focus.* This vulnerability affects Firefox < 121.

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

An attacker could have positioned a `datalist` element to obscure the address bar. This vulnerability affects Firefox < 113, Firefox ESR < 102.11, and Thunderbird < 102.11.

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.

Different techniques existed to obscure the fullscreen notification in Firefox for Android. These could have led to potential user confusion and spoofing attacks. *This bug only affects Firefox for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 126.

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.

A website could have obscured the full screen notification by using the file open dialog. This could have led to user confusion and possible spoofing attacks. *Note: This issue only affected macOS operating systems. Other operating systems are unaffected.* This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

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.

A website could have obscured the fullscreen notification by using a combination of <code>window.open</code>, fullscreen requests, <code>window.name</code> assignments, and <code>setInterval</code> calls. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.

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.

Android applications with unpatched vulnerabilities can be launched from a browser using Intents, exposing users to these vulnerabilities. Firefox will now confirm with users that they want to launch an external application before doing so. <br>*This bug only affects Firefox for Android. Other versions of Firefox are unaffected.*. This vulnerability affects Firefox < 111.

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.

Under certain circumstances, a JavaScript alert (or prompt) could have been shown while another website was displayed underneath it. This could have been abused to trick the user. <br>*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 97.

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.

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.

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.