CVE-2026-12299
MEDIUM severity · CVSS 5.4 · CWE-843
5.4CVSS MEDIUM
Summary
JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
Confidentiality impactLow
Integrity impactLow
Availability impactNone
Exploit probability (EPSS)0%
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Affected products we track (2)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.mozilla.org/security/advisories/mfsa2026-57/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-58/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-59/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-60/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-61/Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=2043139
- https://access.redhat.com/errata/RHSA-2026:27717
- https://access.redhat.com/errata/RHSA-2026:27733