CVE-2025-9181

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.

CVSS 3.1

6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS

0.4% chance of exploitation in the next 30 days; higher than 32% of CVEs (scores of 2026-10-25)

CWE

CWE-457

Published

2025-08-19

Modified

2026-10-05

Record from

the NVD, synced 2026-10-19

Affected

• mozilla:firefox
• mozilla:thunderbird

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1977130
• https://www.mozilla.org/security/advisories/mfsa2025-64/
• https://www.mozilla.org/security/advisories/mfsa2025-66/
• https://www.mozilla.org/security/advisories/mfsa2025-67/
• https://www.mozilla.org/security/advisories/mfsa2025-70/

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