CVE-2025-8037
CRITICAL severity · CVSS 9.1 · CWE-614
9.1CVSS CRITICAL
Summary
Setting a nameless cookie with an equals sign in the value shadowed other cookies. Even if the nameless cookie was set over HTTP and the shadowed cookie included the `Secure` attribute. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactHigh
Availability impactNone
Exploit probability (EPSS)0%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.mozilla.org/security/advisories/mfsa2025-56/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-59/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-61/Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-63/Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1964767