CVE-2025-8037: firefox — Fix

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.

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CVSS v3.1 Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-614 CWE-614

Affected Products

Vendor	Product	Versions
mozilla	firefox	< 140.1
mozilla	firefox	< 141.0
mozilla	thunderbird	< 140.1
mozilla	thunderbird	< 141.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-56/ https://www.mozilla.org/security/advisories/mfsa2025-59/ https://www.mozilla.org/security/advisories/mfsa2025-61/ https://www.mozilla.org/security/advisories/mfsa2025-63/

Other References

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

Frequently Asked Questions

What is CVE-2025-8037? +

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. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2025-8037? +

CVE-2025-8037 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-8037? +

CVE-2025-8037 affects products from mozilla, specifically: firefox, thunderbird. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-8037? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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