CVE-2026-59998

mediumCVSS 4.8covered by 2 sourcesfirst seen 2026-07-02

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

CSIRTS triage

What: An undocumented security-relevant behavior in sshd affects GSSAPIStrictAcceptorCheck when the server is in Windows Active Directory.
Who is affected: Users of OpenSSH before version 10.4 are affected.
Urgency: Remediation is medium due to the medium severity of the vulnerability.
Action: Consider upgrading to OpenSSH version 10.4 or later.

AI-assisted analysis generated from the source advisory — verify against the original.

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Exploitation outlook

Low exploitation risk0.18% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 8% of all EPSS-scored CVEs.

Advisory coverage (2)

mediumCVE-2026-59998: sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAccept…nvd · 2026-07-08
mediumCVE-2026-59998: sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAccept…msrc · 2026-07-02

External references

NVD record for CVE-2026-59998

CVE.org record

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