by Kastro
Paper/Archive/CVE-2026-6771

CVE-2026-6771

Mozilla Firefox — Mitigation bypass in the DOM: Security component

EPSS 0.3%CVSS 9.8
critical.is priorityof 100
34
CVSS 9.8 (ADP)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 23.8.238 × 204.8No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory140.10CNA
Thunderbirdsee advisory140.10CNA

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2025067refmozilla.org/security/advisories/mfsa2026-30refmozilla.org/security/advisories/mfsa2026-32refmozilla.org/security/advisories/mfsa2026-33refmozilla.org/security/advisories/mfsa2026-34