← back
CVE-2025-1933high

JIT corruption of WASM i32 return values on 64-bit CPUs

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.6epss 0.3%
exploitation probability
0.3%top 78% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
Affected products
Mozilla · FirefoxMozilla · Thunderbird
References
https://bugzilla.mozilla.org/show_bug.cgi?id=1946004https://lists.debian.org/debian-lts-announce/2025/03/msg00006.htmlhttps://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/