CVE-2025-4918

An attacker was able to perform an out-of-bounds read or write on a JavaScript `Promise` object. This vulnerability was fixed in Firefox 138.0.4, Firefox ESR 128.10.1, Firefox ESR 115.23.1, Thunderbird 128.10.2, and Thunderbird 138.0.2.

• CWE-125
• CWE-787

• https://bugzilla.mozilla.org/show_bug.cgi?id=1966612Permissions Required
• https://www.mozilla.org/security/advisories/mfsa2025-36/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2025-37/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2025-38/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2025-40/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2025-41/Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2025/05/msg00024.html
• https://lists.debian.org/debian-lts-announce/2025/05/msg00046.html
• https://www.vicarius.io/vsociety/posts/cve-2025-4918-detect-firefox-out-of-bounds-writeExploit, Third Party Advisory
• https://www.vicarius.io/vsociety/posts/cve-2025-4918-mitigate-firefox-out-of-bounds-writeExploit, Third Party Advisory

Published

May 17, 2025

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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