Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mozilla Firefox
115.23.1 to ≤ 115.*unaffected128.10.1 to ≤ 128.*unaffected138.0.4 to ≤ *unaffected
Mozilla Thunderbird
128.10.2 to ≤ 128.*unaffected138.0.2 to ≤ *unaffected
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1966612 ↗
- https://www.mozilla.org/security/advisories/mfsa2025-36/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-37/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-38/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-40/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-41/ ↗
- https://www.vicarius.io/vsociety/posts/cve-2025-4918-detect-firefox-out-of-bounds-write ↗
- https://www.vicarius.io/vsociety/posts/cve-2025-4918-mitigate-firefox-out-of-bounds-write ↗
- https://lists.debian.org/debian-lts-announce/2025/05/msg00046.html ↗
- https://lists.debian.org/debian-lts-announce/2025/05/msg00024.html ↗