Firefox CVE Vulnerabilities

By Mozilla81 known vulnerabilities

Critical
11
High
48
Medium
22
Low
0
None
0

All Firefox CVEs

CVE-2026-8953
9.6 critical

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

May 19, 2026
CVE-2026-8952
8.8 high

Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

May 19, 2026
CVE-2026-8951
6.5 medium

Spoofing issue in the Toolbar component in Firefox for Android. This vulnerability was fixed in Firefox 151.

May 19, 2026
CVE-2026-8950
9.3 critical

Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

May 19, 2026
CVE-2026-8949
7.5 high

Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

May 19, 2026
CVE-2026-8948
9.1 critical

Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

May 19, 2026
CVE-2026-8947
7.3 high

Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

May 19, 2026
CVE-2026-8946
7.5 high

Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

May 19, 2026
CVE-2026-8945
7.5 high

Sandbox escape in Firefox and Firefox Focus for Android. This vulnerability was fixed in Firefox 151.

May 19, 2026
CVE-2026-8391
5.3 medium

Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3.

May 12, 2026
CVE-2026-8390
7.3 high

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150.0.3.

May 12, 2026
CVE-2026-8389
7.3 high

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3.

May 12, 2026
CVE-2026-8388
6.5 medium

Incorrect boundary conditions in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3.

May 12, 2026
CVE-2026-8090
7.3 high

Use-after-free in the DOM: Networking component. This vulnerability was fixed in Firefox 150.0.2, Firefox ESR 140.10.2, Firefox ESR 115.35.2, Thunderbird 150.0.2, and Thunderbird 140.10.2.

May 7, 2026
CVE-2026-7323
7.3 high

Memory safety bugs present in Thunderbird ESR 140.10.0 and Thunderbird 150.0.0. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150.0.1, Firefox ESR 1

Apr 28, 2026
CVE-2026-6784
7.5 high

Memory safety bugs present in Firefox 149 and Thunderbird 149. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6783
5.3 medium

Incorrect boundary conditions, integer overflow in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6782
7.5 high

Information disclosure in the IP Protection component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6781
7.5 high

Denial-of-service in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6780
7.5 high

Denial-of-service in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6779
5.3 medium

Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6778
5.3 medium

Invalid pointer in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6777
5.3 medium

Other issue in the Networking: DNS component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Apr 21, 2026
CVE-2026-6776
7.8 high

Incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

Apr 21, 2026