CVE-2026-12330

Incorrect boundary conditions in the Internationalization component

CVSS 5.4 MEDIUMEPSS 0.2%CWE-119

Vexday Risk Score

13Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 5.4EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

16 Jun 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12.

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

Affected products

Mozilla · Firefox Mozilla · Thunderbird

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2029326 https://www.mozilla.org/security/advisories/mfsa2026-58/https://www.mozilla.org/security/advisories/mfsa2026-59/https://www.mozilla.org/security/advisories/mfsa2026-61/