CVE-2025-5271mediumCWE-116

CVE-2025-5271: medium-severity vulnerability in Mozilla Firefox

Devtools' preview ignored CSP headers

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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