Name: CVE-2026-109729: Use After Free
Creator: Rapid7
Published: 2026-10-13T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-109729, CWE-416, CVSS 5.4, EPSS 0.00242

Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

CVSS Details

CVSS 3.1 Base Score: 5.4
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Mfsa2026 106	—	Upgrade to Mozilla Firefox version 158.0Upgrade to the latest version of Mozilla Firefox	Oct 13, 2026	Oct 13, 2026
Mfsa2026 107	—	Upgrade to Mozilla Firefox ESR version 115.43Upgrade to the latest version of Mozilla Firefox	Oct 13, 2026	Oct 13, 2026
Mfsa2026 108	—	Upgrade to the latest version of Mozilla FirefoxUpgrade to Mozilla Firefox ESR version 153.5	Oct 13, 2026	Oct 13, 2026
Mozilla Thunderbird	—	Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 153.5	Oct 13, 2026	Oct 13, 2026

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CVSS Details

Covered by Rapid7

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