CVE-2026-109766highCWE-693

CVE-2026-109766: high-severity vulnerability in Mozilla Firefox

Mitigation bypass in the Enterprise Policies component

Published 13 Oct 2026 · Updated 19 Oct 2026

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.1epss 0.3%

Mitigation bypass in the Enterprise Policies component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Affected products

Mozilla · Firefox Mozilla · Thunderbird

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References

https://bugzilla.mozilla.org/show_bug.cgi?id=2074406 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/