CVE-2026-109734

Mitigation bypass in the DOM: Security component

State: Published
Severity: 8.1 High
Published: Oct 13, 2026
Updated: Oct 19, 2026
Reserved: Oct 13, 2026

Description

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Scores

CVSS	Score	Vector	Source
3.1	8.1 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N	CISA-ADP

Weaknesses

CWE-693 Protection Mechanism Failure

Affected Products

Product	Versions
FirefoxMozilla	153.5 through 153.*Not affected 158 and laterNot affected
ThunderbirdMozilla	153.5 through 153.*Not affected 158 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1926318
https://www.mozilla.org/security/advisories/mfsa2026-106/
https://www.mozilla.org/security/advisories/mfsa2026-108/
https://www.mozilla.org/security/advisories/mfsa2026-109/
https://www.mozilla.org/security/advisories/mfsa2026-110/

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