Name: CVE-2026-4723: Use After Free
Creator: Rapid7
Published: 2026-03-24T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-4723, CVSS 9.8, EPSS 0.00536

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

CVSS Details

CVSS 3.1 Base Score: 9.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Freebsd	—	Upgrade firefoxUpgrade thunderbird	Mar 27, 2026	Mar 26, 2026
Mfsa2026 20	—	Upgrade to Mozilla Firefox version 149.0Upgrade to the latest version of Mozilla Firefox	Mar 27, 2026	Mar 24, 2026
Mozilla Thunderbird	—	Upgrade to Mozilla Thunderbird version 149.0Upgrade to the latest version of Mozilla Thunderbird	Mar 27, 2026	Mar 24, 2026

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CVSS Details

Covered by Rapid7

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