CVE-2026-109780

CVSS 9.8 (critical) · published 2026-10-13

Mitigation bypass in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

Weakness: CWE-693

Source: NVD CVE-2026-109780

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2072775
• https://www.mozilla.org/security/advisories/mfsa2026-106/
• https://www.mozilla.org/security/advisories/mfsa2026-109/

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