Description
Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Affected products
mozilla: firefox; mozilla: thunderbird
References5
- www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-32/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-34/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2021666 Permissions Required
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 9 · as of 13 November 2026
- CWE
- CWE-693
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