Description
On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mozilla Firefox
115.21 to ≤ 115.*unaffected128.8 to ≤ 128.*unaffected136 to ≤ *unaffected
Mozilla Thunderbird
128.8 to ≤ 128.*unaffected136 to ≤ *unaffected
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1946004 ↗
- https://www.mozilla.org/security/advisories/mfsa2025-14/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-15/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-16/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-17/ ↗
- https://www.mozilla.org/security/advisories/mfsa2025-18/ ↗
- https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html ↗