vulnerability
MFSA2025-42 Firefox: Security Vulnerabilities fixed in Firefox 139 (CVE-2025-5271)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:N/AC:L/Au:N/C:P/I:P/A:N) | May 27, 2025 | May 28, 2025 | Apr 15, 2026 |
Severity
6
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:N)
Published
May 27, 2025
Added
May 28, 2025
Modified
Apr 15, 2026
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.
Solution
mozilla-firefox-upgrade-139_0
Rapid7 Labs
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