CVE-2025-1933
HIGH severity · CVSS 7.6
7.6CVSS HIGH
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
Confidentiality impactLow
Integrity impactLow
Availability impactHigh
Exploit probability (EPSS)0%
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
Affected products we track (2)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.mozilla.org/security/advisories/mfsa2025-14/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-15/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-16/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-17/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-18/Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1946004
- https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html