Mozilla Thunderbird vulnerabilities

CVE-2026-92036 [CRITICAL] CWE-119 CVE-2026-92036: Incorrect boundary conditions in the Networking: HTTP component. This vulnerability was fixed in Fir Incorrect boundary conditions in the Networking: HTTP component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.

CVE-2026-16388 [CRITICAL] CWE-693 CVE-2026-16388: Sandbox escape in the DOM: Networking component. This vulnerability was fixed in Firefox 153 and Thu Sandbox escape in the DOM: Networking component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

CVE-2024-9392 [CRITICAL] CWE-346 CVE-2024-9392: A compromised content process could have allowed for the arbitrary loading of cross-origin pages. Th A compromised content process could have allowed for the arbitrary loading of cross-origin pages. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131.

CVE-2025-8031 [CRITICAL] CWE-276 CVE-2025-8031: The `username:password` part was not correctly stripped from URLs in CSP reports potentially leaking The `username:password` part was not correctly stripped from URLs in CSP reports potentially leaking HTTP Basic Authentication credentials. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

CVE-2026-4691 [CRITICAL] CVE-2026-4691: Use-after-free in the CSS Parsing and Computation component Use-after-free in the CSS Parsing and Computation component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.

CVE-2026-2759 [CRITICAL] CWE-1384 CVE-2026-2759: Incorrect boundary conditions in the Graphics: ImageLib component. This vulnerability was fixed in F Incorrect boundary conditions in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVE-2026-8091 [CRITICAL] CWE-754 CVE-2026-8091: Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed i Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150, Thunderbird 150, Firefox ESR 140.10.1, Thunderbird 140.10.1, and Firefox ESR 115.35.2.

CVE-2026-8094 [CRITICAL] CWE-94 CVE-2026-8094: Other issue in the WebRTC component. This vulnerability was fixed in Firefox ESR 140.10.2 and Thunde Other issue in the WebRTC component. This vulnerability was fixed in Firefox ESR 140.10.2 and Thunderbird 140.10.2.

CVE-2026-4721 [CRITICAL] CWE-120 CVE-2026-4721: Memory safety bugs present in Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox Memory safety bugs present in Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. 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 149, Firefox ESR 115.34, Fire

CVE-2026-4710 [CRITICAL] CWE-119 CVE-2026-4710: Incorrect boundary conditions in the Audio/Video component. This vulnerability was fixed in Firefox Incorrect boundary conditions in the Audio/Video component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

CVE-2026-2793 [CRITICAL] CWE-787 CVE-2026-2793: Memory safety bugs present in Firefox ESR 115.32, Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox Memory safety bugs present in Firefox ESR 115.32, Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox 147 and Thunderbird 147. 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 148, Firefox ESR 115.33, Fire

CVE-2026-5731 [CRITICAL] CWE-119 CVE-2026-5731: Memory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Fi Memory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2, Firef

CVE-2026-16358 [CRITICAL] CWE-346 CVE-2026-16358: Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 1 Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

CVE-2026-16375 [CRITICAL] CWE-346 CVE-2026-16375: Site isolation issue in the Networking: HTTP component. This vulnerability was fixed in Firefox 153, Site isolation issue in the Networking: HTTP component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

CVE-2026-6768 [CRITICAL] CWE-288 CVE-2026-6768: Mitigation bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 150 Mitigation bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

CVE-2026-6760 [CRITICAL] CWE-288 CVE-2026-6760: Mitigation bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 150 Mitigation bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

CVE-2020-15663 [HIGH] CWE-427 CVE-2020-15663: If Firefox is installed to a user-writable directory, the Mozilla Maintenance Service would execute If Firefox is installed to a user-writable directory, the Mozilla Maintenance Service would execute updater.exe from the install location with system privileges. Although the Mozilla Maintenance Service does ensure that updater.exe is signed by Mozilla, the version could have been rolled back to a previous version which would have allowed exploitation

CVE-2026-16412 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16412 Mozilla Foundation Security Advisory 2026-71 CVE: CVE-2026-16412 Product: Thunderbird Impact: high Fixed in: Thunderbird 153

CVE-2026-74986 [CRITICAL] CWE-200 CVE-2026-74986: Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in F Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

CVE-2026-74956 [CRITICAL] CWE-843 CVE-2026-74956: Same-origin policy bypass in the DOM: Service Workers component. This vulnerability was fixed in Fir Same-origin policy bypass in the DOM: Service Workers component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.