CVE-2025-5271

MEDIUM
Published May 27, 2025 Modified Apr 13, 2026 CWE-116

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.

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CVSS v3.1 Score

6.5
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-116 CWE-116

Affected Products

Vendor Product
mozilla firefox

References

Frequently Asked Questions

What is CVE-2025-5271? +
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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2025-5271? +
CVE-2025-5271 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2025-5271? +
CVE-2025-5271 affects products from mozilla, specifically: firefox. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-5271? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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