CVE-2026-2784

CRITICAL 9.8

Mitigation bypass in the DOM: Security component

CVSS Score

9.8

EPSS Score

0.1%

EPSS Percentile

19th

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Vendor	mozilla
Product	firefox
Ecosystems	Browser JavaScript
Industries	Technology
Published	Feb 24, 2026
Last Updated	Apr 16, 2026

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Affected Versions

Mozilla / Firefox

All versions affected

Mozilla / Thunderbird

All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗

bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2012984 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-13/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-15/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-16/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-17/

Credits

D. Santos