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CVE-2026-59998 (GCVE-0-2026-59998)

Vulnerability from cvelistv5 – Published: 2026-07-08 00:11 – Updated: 2026-07-08 13:48
VLAI
Summary
sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no value if the server is in Windows Active Directory.
Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 13:47 UTC
CWE
  • CWE-573 - Improper Following of Specification by Caller
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenBSD OpenSSH Affected: 0 , < 10.4 (custom)
    cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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