Description
Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Affected products
mozilla: firefox; mozilla: thunderbird
References7
- www.mozilla.org/security/advisories/mfsa2026-74/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-76/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-77/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-78/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-79/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-80/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2051897 Permissions Required
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 26 · as of 11 November 2026
- CWE
- CWE-693
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