Windows Server 2025 OpenSSH private host key files must conform to minimum requirements.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-285321SRG-OS-000480-GPOS-00227WN25-SH-000090SV-285321r1211191_rule2026-05-281

Description

If an unauthorized user obtains the private SSH host key file, the host could be impersonated.

ℹ️ Check

If OpenSSH is not installed on the system, this requirement is not applicable. Verify the SSH private host key files permissions with the following command: C:\ > Get-ChildItem -Path "C:\ProgramData\ssh" -Filter "*_key" -File | ForEach-Object { icacls.exe $_.FullName } C:\ProgramData\ssh\ssh_host_ecdsa_key BUILTIN\Administrators:(F) NT AUTHORITY\SYSTEM:(F) Successfully processed 1 files; Failed processing 0 files C:\ProgramData\ssh\ssh_host_ed25519_key BUILTIN\Administrators:(F) NT AUTHORITY\SYSTEM:(F) Successfully processed 1 files; Failed processing 0 files C:\ProgramData\ssh\ssh_host_rsa_key BUILTIN\Administrators:(F) NT AUTHORITY\SYSTEM:(F) Successfully processed 1 files; Failed processing 0 files If any private host key file does not have the default permission as in the example output, this is a finding.

✔️ Fix

Maintain the permissions of the private host key files as follows: BUILTIN\Administrators:(F) NT AUTHORITY\SYSTEM:(F)