CVE-2025-9181

Name: CVE-2025-9181
Creator: NVD / NIST
Published: 2025-08-19T21:15:30.52+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.34%

Last modified Jun 17, 2026

CVE-2025-9181 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.. EPSS estimates a 0.34% chance of exploitation in the next 30 days.

Description

Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

0.34%

25.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-457

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 128.14.0
Mozilla	Firefox	< 142.0
Mozilla	Firefox	>= 140.0, < 140.2.0
Mozilla	Thunderbird	< 128.14.0
Mozilla	Thunderbird	< 142.0
Mozilla	Thunderbird	>= 140.0, < 140.2.0

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1977130Issue Tracking, Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-64/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-66/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-67/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-70/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-71/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-72/Vendor Advisory
https://lists.debian.org/debian-lts-announce/2025/08/msg00016.html
https://lists.debian.org/debian-lts-announce/2025/08/msg00018.html

Timeline

Published: Aug 19, 2025
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2025-9181?

How severe is CVE-2025-9181?

CVE-2025-9181 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2025-9181?

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-2025-9181?

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

Scan your code now

Source: NVD / NIST