PT-2026-27383 · Mozilla · Firefox+1

Oskar L · Published 2026-03-24 · Updated 2026-03-24 · CVE-2026-4684

NVD

CVSS v3.1

7.5

High

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

Race condition, use-after-free in the Graphics: WebRender component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9.

Fix

Race Condition

Use After Free

Weakness Enumeration

CWE-362

CWE-416

Related Identifiers

CVE-2026-4684

Affected Products

Firefox

Firefox Esr

References · 5

• https://mozilla.org/security/advisories/mfsa2026-21 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-20 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-22 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-4684 · Security Note
• https://bugzilla.mozilla.org/show_bug.cgi?id=2011129 · Note