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.

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Advisories
Source ID Title
EUVD EUVD EUVD-2025-18105 Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139.
Ubuntu USN Ubuntu USN USN-7991-1 Thunderbird vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 13 Apr 2026 15:00:00 +0000

Type Values Removed Values Added
Description Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139. 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.

Thu, 30 Oct 2025 16:30:00 +0000

Type Values Removed Values Added
Title firefox: Devtools' preview ignored CSP headers Devtools' preview ignored CSP headers

Wed, 11 Jun 2025 12:15:00 +0000

Type Values Removed Values Added
Description Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139. Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139 and Thunderbird < 139.
References

Wed, 28 May 2025 19:00:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
Vendors & Products Mozilla
Mozilla firefox

Wed, 28 May 2025 14:45:00 +0000

Type Values Removed Values Added
Title firefox: Devtools' preview ignored CSP headers
Weaknesses CWE-807
References
Metrics threat_severity

None

threat_severity

Low


Tue, 27 May 2025 18:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-116
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 27 May 2025 12:45:00 +0000

Type Values Removed Values Added
Description Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This vulnerability affects Firefox < 139.
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-04-13T14:30:48.968Z

Reserved: 2025-05-27T12:29:29.015Z

Link: CVE-2025-5271

cve-icon Vulnrichment

Updated: 2025-05-27T17:37:27.980Z

cve-icon NVD

Status : Modified

Published: 2025-05-27T13:15:22.923

Modified: 2026-04-13T15:17:05.267

Link: CVE-2025-5271

cve-icon Redhat

Severity : Low

Publid Date: 2025-05-27T12:29:29Z

Links: CVE-2025-5271 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses