{"affected":[{"affectedData":[{"product":"Firefox","vendor":"Mozilla","versions":[{"lessThanOrEqual":"*","status":"unaffected","version":"139","versionType":"rpm"}]},{"product":"Thunderbird","vendor":"Mozilla","versions":[{"lessThanOrEqual":"*","status":"unaffected","version":"139","versionType":"rpm"}]}],"source":"security@mozilla.org"}],"configurations":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*","matchCriteriaId":"82C74587-41B7-49DB-8B9D-99DE41506023","versionEndExcluding":"139.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"cveTags":[],"descriptions":[{"lang":"en","value":"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."},{"lang":"es","value":"La vista previa de una respuesta en DevTools ignoraba los encabezados CSP, lo que podría haber permitido ataques de inyección de contenido. Esta vulnerabilidad afecta a Firefox anterior a la versión 139."}],"id":"CVE-2025-5271","lastModified":"2026-09-30T18:10:00.190","metrics":{"cvssMetricV31":[{"cvssData":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","version":"3.1"},"exploitabilityScore":3.9,"impactScore":2.5,"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary"}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"id":"CVE-2025-5271","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","timestamp":"2025-05-27T17:36:12.567350Z","version":"2.0.3"}}]},"published":"2025-05-27T13:15:22.923","references":[{"source":"security@mozilla.org","tags":["Permissions Required"],"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1920348"},{"source":"security@mozilla.org","tags":["Vendor Advisory"],"url":"https://www.mozilla.org/security/advisories/mfsa2025-42/"},{"source":"security@mozilla.org","url":"https://www.mozilla.org/security/advisories/mfsa2025-45/"}],"sourceIdentifier":"security@mozilla.org","vulnStatus":"Modified","weaknesses":[{"description":[{"lang":"en","value":"CWE-116"}],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary"}]}