Paper/Archive/CVE-2026-4724

CVE-2026-4724

Mozilla Firefox — Undefined behavior in the Audio/Video component

EPSS 0.5%CVSS 9.1

critical.is priorityof 100

36

CVSS 9.1 (ADP, NVD agree)9.1 / 10 × 3027.3 Not in CISA KEV+300.0 EPSS percentile 43.3.433 × 208.7 No public exploit+100.0 SSVC exploitation: none+100.0

Description · from the CVE record

Undefined behavior in the Audio/Video component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

Affected

ProductAffectedFixed inSource

Firefoxsee advisory149CNA

Thunderbirdsee advisory149CNA

Scores by source

CISA ADP9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

NVD9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2014865 refmozilla.org/security/advisories/mfsa2026-20 refmozilla.org/security/advisories/mfsa2026-23