Name: CVE-2026-88647: Improper Validation of Certificate with Host Mismatch
Creator: Rapid7
Published: 2026-10-08T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-88647, CWE-297, CVSS 9.1, EPSS 0.00212

A hostname verification bypass in GnuTLS v3.8.13 allows attackers to circumvent the Common Name fallback mechanism and eavesdrop on communications via a crafted certificate.

CVSS Details

CVSS 3.1 Base Score: 9.1
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Redhat_linux	—	No solution exists	Oct 13, 2026	Oct 8, 2026

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CVSS Details

Covered by Rapid7

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