Firefox vulnerabilities

870 known vulnerabilities in Firefox from Mozilla. 869 are rated high or critical, and 15 have been exploited in real attacks. Each entry lists the affected versions and the release that fixes it, where the vendor has published one.

870vulnerabilities

253critical

616high

15exploited

8.7average CVSS score

Latest first

8.8 High severity
Firefox: Improper Privilege Management
CVE-2026-124951Nov 10, 2026Mozilla
Privilege escalation in the Nimbus Desktop Client component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
CVE-2026-124948Nov 10, 2026Mozilla
Incorrect boundary conditions, use-after-free in the Graphics component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124926Nov 10, 2026Mozilla
Incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124924Nov 10, 2026Mozilla
Incorrect boundary conditions in the Graphics: WebRender component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124922Nov 10, 2026Mozilla
Use-after-free in the CSS Transitions and Animations component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124919Nov 10, 2026Mozilla
Privilege escalation due to use-after-free in the WebRTC: Networking component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124918Nov 10, 2026Mozilla
Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
9.6 Critical severity
Firefox: Use After Free
CVE-2026-124917Nov 10, 2026Mozilla
Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124915Nov 10, 2026Mozilla
Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124907Nov 10, 2026Mozilla
Privilege escalation, sandbox escape due to use-after-free in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124906Nov 10, 2026Mozilla
Use-after-free in the Graphics: WebRender component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
9.6 Critical severity
Firefox: Use After Free
CVE-2026-124903Nov 10, 2026Mozilla
Sandbox escape due to use-after-free in the IPC component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124899Nov 10, 2026Mozilla
Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124898Nov 10, 2026Mozilla
Use-after-free in the DOM: Editor component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124897Nov 10, 2026Mozilla
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124895Nov 10, 2026Mozilla
Use-after-free in the Storage: localStorage & sessionStorage component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124894Nov 10, 2026Mozilla
Use-after-free in the Networking: Cookies component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124892Nov 10, 2026Mozilla
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124891Nov 10, 2026Mozilla
Incorrect boundary conditions in the DOM: Selection component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124890Nov 10, 2026Mozilla
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124889Nov 10, 2026Mozilla
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124888Nov 10, 2026Mozilla
Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124887Nov 10, 2026Mozilla
Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124885Nov 10, 2026Mozilla
Use-after-free in the Graphics: Text component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124884Nov 10, 2026Mozilla
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124883Nov 10, 2026Mozilla
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124882Nov 10, 2026Mozilla
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124881Nov 10, 2026Mozilla
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124880Nov 10, 2026Mozilla
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124877Nov 10, 2026Mozilla
Use-after-free in the Layout: Positioned component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124876Nov 10, 2026Mozilla
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124875Nov 10, 2026Mozilla
Incorrect boundary conditions in the DOM: CSS Object Model component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124872Nov 10, 2026Mozilla
Use-after-free in the Cycle Collector component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124870Nov 10, 2026Mozilla
Incorrect boundary conditions in the JavaScript: GC component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124869Nov 10, 2026Mozilla
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Buffer Copy without Checking Size of Input
CVE-2026-124868Nov 10, 2026Mozilla
Incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124865Nov 10, 2026Mozilla
Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
9.6 Critical severity
Firefox: Use After Free
CVE-2026-124864Nov 10, 2026Mozilla
Sandbox escape due to use-after-free in the DOM: Service Workers component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124863Nov 10, 2026Mozilla
Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
8.8 High severity
Firefox: Use After Free
CVE-2026-124862Nov 10, 2026Mozilla
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.