🔐 CVE Alert

CVE-2025-5271

MEDIUM 6.5

Devtools' preview ignored CSP headers

CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th

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.

Vendor mozilla
Product firefox
Ecosystems
Industries
Technology
Published May 27, 2025
Last Updated Apr 13, 2026
Stay Ahead of the Next One

Get instant alerts for mozilla firefox

Be the first to know when new medium vulnerabilities affecting mozilla firefox are published — delivered to Slack, Telegram or Discord.

Get Free Alerts → Free · No credit card · 60 sec setup

Affected Versions

Mozilla / Firefox
All versions affected
Mozilla / Thunderbird
All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=1920348 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-42/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-45/

Credits

Satoki Tsuji