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CVE-2025-5271

Medium

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.

SeverityMedium
CVSS6.5
Exploit probability—
ProductMozilla Firefox
PublishedMay 27, 2025
First seenMay 27, 2025
Weakness typeCWE-116CWE-116

How to fix

Update
  • mozilla firefox139.0 or later

Affected products

ProductAffected versionsFixed in
mozilla firefoxv < 139.0139.0

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