CVE-2025-5271
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
Previewing a response in Devtools ignored CSP headers, which could have allowed content injection attacks. This was fixed in Firefox 139 and Thunderbird 139.
Risk Assessment
An attacker could exploit this to inject malicious content, potentially leading to XSS or other security breaches.
Recommendation
Update Firefox or Thunderbird to version 139 or later to get the fix.
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Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS