The open-source standard for secure remote logins, tunneling and file transfers.
OpenSSH is the reference open-source implementation of the SSH-2 protocol, developed and maintained by the OpenBSD project. It ships by default with virtually every Linux distribution, the BSDs and macOS, and an official Windows port is maintained by Microsoft. If you have ever opened a terminal and typed ssh to reach a server, you have almost certainly used it.
The toolkit covers the full remote-access workflow: the ssh client for encrypted remote shells, the sshd server daemon, scp and sftp for secure file transfers, ssh-keygen for key pairs, and ssh-agent for key management. On top of simple logins, it handles port forwarding (local, remote and dynamic), SOCKS tunneling, X11 forwarding, jump hosts and certificate-based authentication. Everything is driven by well-documented configuration files and endless scriptability, which is why it remains the backbone of remote administration two decades in.
OpenSSH is free software under the BSD license, with a portable release (OpenBSD's code plus compatibility glue) tracked at openssh.com. The project has recently moved to more frequent releases: its notes explain that security bugs are now often rediscovered independently, including by AI tools, so fixes ship as soon as they are ready rather than waiting for a scheduled batch. The latest example is 10.6p2 (November 5, 2026), an emergency workaround for a critical password authentication bypass affecting Linux systems built on musl libc with PAM disabled, such as Alpine Linux's default openssh-server package. glibc-based distributions and PAM-enabled setups are not affected. We covered the flaw, who is exposed and how to patch in our news article: OpenSSH Fixes a Critical Login Flaw.
Full SSH-2 client and server (sshd) for encrypted terminal sessions.
Copy files with scp or run interactive transfers over sftp.
Local, remote and dynamic (SOCKS) forwarding to reach anything, anywhere.
sshd_config options like AllowUsers, Match blocks and PermitRootLogin.
Yes. OpenSSH is open-source software under the BSD license, maintained by the OpenBSD project, and free for any use, personal or commercial.
Only on Linux systems built with musl libc and PAM disabled, such as Alpine Linux's openssh-server package. Version 10.6p2 fixes it; glibc-based distributions and PAM-enabled setups were not affected. See our news article for the full picture and patch instructions.
Yes. An official port of OpenSSH ships with Windows as an optional feature, both client and server, alongside the macOS and Linux versions.