TinySSH

Spec sheet

Product

TinySSH is a minimal SSH server that implements a subset of SSHv2 features.Read 11 Oct 2026 · tinyssh.org

Integrations

The project documents running TinySSH with tcpserver, systemd socket activation, inetd, and BusyBox tcpsvd.Read 11 Oct 2026 · github.com

License

The project says TinySSH is in the public domain.Read 11 Oct 2026 · tinyssh.org

Founded

2014Read 28 Sep 2026 · tinyssh.org

Authentication

TinySSH supports public-key authentication and does not implement password or host-based authentication.Read 11 Oct 2026 · tinyssh.org

Authorized keys

OpenSSH authorized_keys entries are supported only when they contain a key without options.Read 11 Oct 2026 · tinyssh.org

Code size

The project says its 20240101 release contains 63,899 words of code.Read 11 Oct 2026 · tinyssh.org

Compatibility limits

TinySSH does not implement SSH1, compression, port forwarding, agent forwarding, or X11 forwarding.Read 11 Oct 2026 · github.com

Cryptography

The project lists Ed25519 host keys, Curve25519 key exchange, ChaCha20-Poly1305, and post-quantum sntrup761x25519 key exchange support.Read 11 Oct 2026 · github.com

Downloads

The install page documents source downloads and compilation for Unix, plus installation from Debian's apt package.Read 11 Oct 2026 · tinyssh.org

File transfer

TinySSH has no SCP program; its FAQ says rsync over SSH can do the same job and that an external SFTP server can be run with the -x switch.Read 11 Oct 2026 · tinyssh.org

Installation

The install page gives Debian package installation instructions and Unix source compilation instructions.Read 11 Oct 2026 · tinyssh.org

Key compatibility

TinySSH accepts OpenSSH authorized_keys entries containing keys only, without options, and its FAQ says OpenSSH private keys require conversion to TinySSH format.Read 11 Oct 2026 · tinyssh.org

Memory

The project says it uses statically allocated memory of less than 1 MB.Read 11 Oct 2026 · tinyssh.org

Release status

The project identifies its current release as 20240101 and labels it beta.Read 11 Oct 2026 · tinyssh.org

Security change

Starting with version 20260906, TinySSH rejects client-supplied environment variables in env channel requests.Read 11 Oct 2026 · github.com

Security design

TinySSH says it omits older cryptographic primitives including RSA, DSA, HMAC-MD5, HMAC-SHA1, 3DES, and RC4.Read 11 Oct 2026 · github.com

SFTP

TinySSH can run an external SFTP server such as OpenSSH sftp-server when configured with the -x switch.Read 11 Oct 2026 · tinyssh.org

Windows

The FAQ says TinySSH can be compiled and run on Windows through Cygwin.Read 11 Oct 2026 · tinyssh.org

Where Specifiction places it

• SSH Server Software#29 of 346.8