CVE-2025-1933

Name: CVE-2025-1933
Creator: NVD / NIST
Published: 2025-03-04T14:15:38.17+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.6/10EPSS 0.29%

Last modified Jun 17, 2026

CVE-2025-1933 is a high-severity vulnerability rated 7.6/10 on the CVSS scale. 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. EPSS estimates a 0.29% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.6/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H

EPSS Probability

0.29%

21.1th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 115.21.0
Mozilla	Firefox	< 136.0
Mozilla	Firefox	>= 116.0, < 128.8.0
Mozilla	Thunderbird	< 128.8
Mozilla	Thunderbird	>= 129.0, < 136.0

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1946004Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2025-14/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-15/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-16/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-17/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-18/Vendor Advisory
https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html

Timeline

Published: Mar 4, 2025
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2025-1933?

How severe is CVE-2025-1933?

CVE-2025-1933 has a CVSS score of 7.6/10 (HIGH severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.

How do I fix CVE-2025-1933?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-1933?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST