PT-2026-27390 · Mozilla · Firefox+1

Fabius Artrel · Published 2026-03-24 · Updated 2026-03-24 · CVE-2026-4691

NVD

Use-after-free in the CSS Parsing and Computation component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9.

Related Identifiers

CVE-2026-4691

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-2026-4691 · Security Note
• https://bugzilla.mozilla.org/show_bug.cgi?id=2017512 · Note