Ssh.exe is the OpenSSH compatible client can be used to connect to Windows 10 (build 1809 and later) and Windows Server 2019 devices.
ssh localhost calc.exe
Execute calc.exe on host machine. The prompt for password can be eliminated by adding the host's public key in the user's authorized_keys file. Adversaries can do the same for execution on remote machines.
Execute specified command, can be used for defense evasion.
c:\windows\system32\OpenSSH\ssh.exe
Sigma: https://github.com/SigmaHQ/sigma/blob/c04bef2fbbe8beff6c7620d5d7ea6872dbe7acba/rules/windows/process_creation/proc_creation_win_lolbin_ssh.yml, IOC: Event ID 4624 with process name C:\Windows\System32\OpenSSH\sshd.exe., IOC: command line arguments specifying execution.
Akshat Pradhan, Felix Boulet