Description
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability was fixed in Firefox 139 and Thunderbird 139.
Affected products
mozilla: firefox
References3
- www.mozilla.org/security/advisories/mfsa2025-42/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1920348 Permissions Required
- www.mozilla.org/security/advisories/mfsa2025-45/
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: 23 · as of 7 November 2026
- CWE
- CWE-116
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