CVE-2026-100828

Mitigation bypass in the Bookmarks & History component

Mitigation bypass in the Bookmarks & History component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

CVSS 3.1 · 9.6 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-100829

Mitigation bypass in the DOM: Security component

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

CVSS 3.1 · 9.6 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-100830

Mitigation bypass in the DOM: Navigation component

Mitigation bypass in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-100831

Use-after-free in the DOM: UI Events & Focus Handling component

Use-after-free in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-103418

Universal XSS via the HTML language attribute in Translation Services

Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox For Ios

CVE-2011-3389

HTTPS: block-wise chosen-plaintext attack against SSL/TLS (BEAST)

The SSL protocol, as used in certain configurations in Microsoft Windows and Microsoft Internet Explorer, Mozilla Firefox, Google Chrome, Opera, and other products, encrypts data by using CBC mode with chained initialization vectors, which allows man-in-the-middle attackers to obtain plaintext HTTP headers via a blockwise chosen-boundary attack (BCBA) on an HTTPS session, in conjunction with JavaScript code that uses (1) the HTML5 WebSocket API, (2) the Java URLConnection API, or (3) the Silverlight WebClient API, aka a "BEAST" attack.

CVSS 2.0 · 4.3 Medium EPSS 73.3% KEV · Not listed

Vendors

Canonical Debian Google and 6 more

Products

Ubuntu Linux Debian Linux Chrome and 18 more

CVE-2026-106550

CVE-2026-106550

Mozilla's Node-convict (version 6.2.2 and later) is vulnerable to a Denial of Service vulnerability caused by incomplete prototype‑pollution protections in config.set(). An attacker controlling the configuration key can write arbitrary properties to constructor.<key>, which walk() resolves to the global Object function. This allows overwriting core JavaScript methods such as Object.assign, leading to persistent process-wide failures and requiring a restart. The issue bypasses existing filters that only block constructor.prototype.* and __proto__.*. Exploitation requires an endpoint that forwards attacker-controlled keys into config.set().

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Convict

CVE-2016-9063

firefox: Possible integer overflow to fix inside XML_Parse in Expat

An integer overflow during the parsing of XML using the Expat library. This vulnerability affects Firefox < 50.

CVSS 3.1 · 9.8 Critical EPSS 5.4% KEV · Not listed

Vendors

Debian Mozilla Python

Products

Debian Linux Firefox Python

CVE-2016-0718

expat: Out-of-bounds heap read on crafted input causing crash

Expat allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a malformed input document, which triggers a buffer overflow.

CVSS 3.1 · 9.8 Critical EPSS 13.3% KEV · Not listed

Vendors

Apple Canonical Debian and 7 more

Products

Mac Os X Ubuntu Linux Debian Linux and 13 more

CVE-2024-9398

firefox: thunderbird: External protocol handlers could be enumerated via popups

By checking the result of calls to `window.open` with specifically set protocol handlers, an attacker could determine if the application which implements that protocol handler is installed. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Thunderbird < 128.3, and Thunderbird < 131.

CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2026-100817

Other issue in the JavaScript: WebAssembly component

Other issue in the JavaScript: WebAssembly component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92025

Use-after-free in the DOM: Navigation component

Use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92026

Use-after-free in the Networking component

Use-after-free in the Networking component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92027

Use-after-free in the DOM: Streams component

Use-after-free in the DOM: Streams component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92028

Use-after-free in the DOM: Core & HTML component

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92029

Use-after-free in the SVG component

Use-after-free in the SVG component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92030

Mitigation bypass in the DOM: Copy & Paste and Drag & Drop component

Mitigation bypass in the DOM: Copy & Paste and Drag & Drop component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92031

Information disclosure in the Graphics: ImageLib component

Information disclosure in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 156, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92006

Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-92007

Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component

Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird