by Kastro
Paper/Archive/CVE-2026-2784

CVE-2026-2784

Mozilla Firefox — Mitigation bypass in the DOM: Security component

EPSS 0.5%CVSS 9.8
critical.is priorityof 100
38
CVSS 9.8 (ADP, NVD agree)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 42.1.421 × 208.4No 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 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory140.8CNA
Thunderbirdsee advisory140.8CNA

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD9.8CVSS: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=2012984refmozilla.org/security/advisories/mfsa2026-13refmozilla.org/security/advisories/mfsa2026-15refmozilla.org/security/advisories/mfsa2026-16refmozilla.org/security/advisories/mfsa2026-17