Name: CVE-2026-59998: Improper Following of Specification by Caller
Creator: Rapid7
Published: 2026-07-08T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-59998, CWE-573, CVSS 6.5, EPSS 0.0018

sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no value if the server is in Windows Active Directory.

CVSS Details

CVSS 3.1 Base Score: 6.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade openssh	Sep 1, 2026	Jul 8, 2026
Openbsd Openssh	—	Upgrade to OpenSSH version 10.4	Aug 18, 2026	Jul 8, 2026
Redhat_linux	—	No solution exists	Jul 17, 2026	Jul 8, 2026
Ubuntu	—	Upgrade openssh-server (Ubuntu Pro)Upgrade openssh-serverUpgrade openssh-clientUpgrade openssh-client (Ubuntu Pro)	Jul 13, 2026	Jul 8, 2026
Vmware Photon_os	—	Use 'tdnf update' to upgrade all packages to the latest version.	Jul 22, 2026	Jul 8, 2026

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CVSS Details

Covered by Rapid7

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