PT-2026-49668 · Mozilla · Firefox

Hyeonjun Ahn · Published 2026-06-16 · Updated 2026-06-16 · CVE-2026-12299

NVD

CVSS v3.1

5.4

Medium

Base vector

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

JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37.

Fix

Type Confusion

Weakness Enumeration

CWE-843

Related Identifiers

CVE-2026-12299

Affected Products

Firefox

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-12299 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-59 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-57 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-58 · Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=2043139 · Note