Mozilla Corporation

In addition to detecting when a user was taking a screenshot (XXX), a website was able to overlay the 'My Shots' button that appeared, and direct the user to a replica Firefox Screenshots page that could be used for phishing. This vulnerability affects Firefox < 127.

If the `browser.privatebrowsing.autostart` preference is enabled, IndexedDB files were not properly deleted when the window was closed. This preference is disabled by default in Firefox. This vulnerability affects Firefox < 126, Firefox ESR < 115.11, and Thunderbird < 115.11.

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…

Dragging Javascript URLs to the address bar could cause them to be loaded, bypassing restrictions and security protections This vulnerability affects Firefox for iOS < 124.

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.

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.

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.

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.

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.

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.

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…

Multiple NSS NIST curves were susceptible to a side-channel attack known as "Minerva". This attack could potentially allow an attacker to recover the private key. This vulnerability affects Firefox < 121.

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…

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…

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.

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…

A malicious installed WebExtension could open arbitrary URLs, which under the right circumstance could be leveraged to collect sensitive user data. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

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.

Excel `.xll` add-in files did not have a blocklist entry in Firefox's executable blocklist which allowed them to be downloaded without any warning of their potential harm. This vulnerability affects Firefox < 117, Firefox ESR < 102.15, Firefox ESR < 115.2, Thunderbird < 102.15,…

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.

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.

Under specific circumstances a WebExtension may have received a jar:file:/// URI instead of a moz-extension:/// URI during a load request. This leaked directory paths on the user's machine. This vulnerability affects Firefox for Android < 112, Firefox <…

A website could have obscured the fullscreen notification by using a combination of window.open, fullscreen requests, window.name assignments, and setInterval calls. This could have led to user confusion and possible spoofing attacks. This…

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

Under certain circumstances, a ServiceWorker's offline cache may have leaked to the file system when using private browsing mode. 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. *This bug only affects Firefox for…

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

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.

Service Workers did not detect Private Browsing Mode correctly in all cases, which could have led to Service Workers being written to disk for websites visited in Private Browsing Mode. This would not have persisted them in a state where they would run again, but it would have…

When receiving an HTML email that specified to load an iframe 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.

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.*This bug…

When loading a script with Subresource Integrity, attackers with an injection capability could trigger the reuse of previously cached entries with incorrect, different integrity metadata. This vulnerability affects Firefox < 103.

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.

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

The Performance API did not properly hide the fact whether a request cross-origin resource has observed redirects. This vulnerability affects Firefox < 100.

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.

While the text displayed in Autofill tooltips cannot be directly read by JavaScript, the text was rendered using page fonts. Side-channel attacks on the text by using specially crafted fonts could have lead to this text being inferred by the webpage. This vulnerability affects…

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. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This…

When scanning QR codes, Firefox for Android would have allowed navigation to some URLs that do not point to web content.*This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 96.

When navigating from inside an iframe while requesting fullscreen access, an attacker-controlled tab could have made the browser unable to leave fullscreen mode. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

When viewing an email message A, which contains an attached message B, where B is encrypted or digitally signed or both, Thunderbird may show an incorrect encryption or signature status. After opening and viewing the attached message B, when returning to the display of message…

If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. *This bug only affects Firefox for Android. Other operating systems are unaffected.**Note*: Due to a…

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.

By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR <…

When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing. This vulnerability affects Firefox < 94.

When a user loaded a Web Extensions context menu, the Web Extension could access the post-redirect URL of the element clicked. If the Web Extension lacked the WebRequest permission for the hosts involved in the redirect, this would be a same-origin-violation leaking data the Web…

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…

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…

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.

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.)…