CVE-2025-8037

Description

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.

PUBLISHED Reserved 2025-07-22 | Published 2025-07-22 | Updated 2026-04-13 | Assigner mozilla

Product status

Credits

Uku Sõrmus

References

bugzilla.mozilla.org/show_bug.cgi?id=1964767

www.mozilla.org/security/advisories/mfsa2025-56/

www.mozilla.org/security/advisories/mfsa2025-59/

www.mozilla.org/security/advisories/mfsa2025-61/

www.mozilla.org/security/advisories/mfsa2025-63/

cve.org (CVE-2025-8037)

nvd.nist.gov (CVE-2025-8037)

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