Packages and Binaries:

openssh-client

Secure shell (SSH) client, for secure access to remote machines
This is the portable version of OpenSSH, a free implementation of the Secure Shell protocol as specified by the IETF secsh working group.

Ssh (Secure Shell) is a program for logging into a remote machine and for executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It can be used to provide applications with a secure communication channel.

This package provides the ssh, scp and sftp clients, the ssh-agent and ssh-add programs to make public key authentication more convenient, and the ssh-keygen, ssh-keyscan, ssh-copy-id and ssh-argv0 utilities.

In some countries it may be illegal to use any encryption at all without a special permit.

ssh replaces the insecure rsh, rcp and rlogin programs, which are obsolete for most purposes.

Installed size: 4.11 MB
How to install: sudo apt install openssh-client

scp

OpenSSH secure file copy

root@kali:~# scp -h
scp: unknown option -- h
usage: scp [-346ABCOpqRrsTv] [-c cipher] [-D sftp_server_path] [-F ssh_config]
           [-i identity_file] [-J destination] [-l limit] [-o ssh_option]
           [-P port] [-S program] [-X sftp_option] source ... target

sftp

OpenSSH secure file transfer

root@kali:~# sftp --help
unknown option -- -
usage: sftp [-46AaCfNpqrv] [-B buffer_size] [-b batchfile] [-c cipher]
          [-D sftp_server_command] [-F ssh_config] [-i identity_file]
          [-J destination] [-l limit] [-o ssh_option] [-P port]
          [-R num_requests] [-S program] [-s subsystem | sftp_server]
          [-X sftp_option] destination

ssh

OpenSSH remote login client

root@kali:~# ssh -h
unknown option -- h
usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface] [-b bind_address]
           [-c cipher_spec] [-D [bind_address:]port] [-E log_file]
           [-e escape_char] [-F configfile] [-I pkcs11] [-i identity_file]
           [-J destination] [-L address] [-l login_name] [-m mac_spec]
           [-O ctl_cmd] [-o option] [-P tag] [-p port] [-R address]
           [-S ctl_path] [-W host:port] [-w local_tun[:remote_tun]]
           destination [command [argument ...]]
       ssh [-Q query_option]

ssh-add

Adds private key identities to the OpenSSH authentication agent

root@kali:~# man ssh-add
SSH-ADD(1)                   General Commands Manual                 SSH-ADD(1)

NAME
     ssh-add -- adds private key identities to the OpenSSH authentication agent

SYNOPSIS
     ssh-add [-CcDdKkLlNqvXx] [-E fingerprint_hash] [-H hostkey_file]
             [-h destination_constraint] [-S provider] [-t life] [file ...]
     ssh-add -s pkcs11 [-Cv] [certificate ...]
     ssh-add -e pkcs11
     ssh-add -T pubkey ...
     ssh-add -Q

DESCRIPTION
     ssh-add  adds  private  key  identities  to the authentication agent, ssh-
     agent(1).  When run without arguments, it adds  the  files  ~/.ssh/id_rsa,
     ~/.ssh/id_ecdsa,       ~/.ssh/id_ecdsa_sk,      ~/.ssh/id_ed25519      and
     ~/.ssh/id_ed25519_sk.  After loading a private key, ssh-add  will  try  to
     load  corresponding  certificate information from the filename obtained by
     appending -cert.pub to the name of the private key file.  Alternative file
     names can be given on the command line.

     If any file requires a passphrase, ssh-add asks for  the  passphrase  from
     the  user.   The  passphrase is read from the user's tty.  ssh-add retries
     the last passphrase if multiple identity files are given.

     The authentication agent must be running and the SSH_AUTH_SOCK environment
     variable must contain the name of its socket for ssh-add to work.

     The options are as follows:

     -C      When loading keys into or deleting keys from  the  agent,  process
             certificates only and skip plain keys.

     -c      Indicates  that added identities should be subject to confirmation
             before being used for authentication.  Confirmation  is  performed
             by  ssh-askpass(1).  Successful confirmation is signaled by a zero
             exit status from ssh-askpass(1), rather than text entered into the
             requester.

     -D      Deletes all identities from the agent.

     -d      Instead of adding identities, removes identities from  the  agent.
             If  ssh-add  has  been run without arguments, the keys for the de-
             fault identities and their corresponding certificates will be  re-
             moved.  Otherwise, the argument list will be interpreted as a list
             of  paths  to public key files to specify keys and certificates to
             be removed from the agent.  If no public key is found at  a  given
             path,  ssh-add  will  append .pub and retry.  If the argument list
             consists of "-" then ssh-add will read public keys to  be  removed
             from standard input.

     -E fingerprint_hash
             Specifies  the  hash  algorithm  used  when displaying key finger-
             prints.  Valid options are: "md5" and "sha256".   The  default  is
             "sha256".

     -e pkcs11
             Remove keys provided by the PKCS#11 shared library pkcs11.

     -H hostkey_file
             Specifies a known hosts file to look up hostkeys when using desti-
             nation-constrained keys via the -h flag.  This option may be spec-
             ified  multiple  times to allow multiple files to be searched.  If
             no files are specified, ssh-add will use the default ssh_config(5)
             known  hosts   files:   ~/.ssh/known_hosts,   ~/.ssh/known_hosts2,
             /etc/ssh/ssh_known_hosts, and /etc/ssh/ssh_known_hosts2.

     -h destination_constraint
             When  adding  keys,  constrain them to be usable only through spe-
             cific hosts or to specific destinations.

             Destination constraints of the form `[user@]dest-hostname'  permit
             use  of  the  key  only from the origin host (the one running ssh-
             agent(1)) to the listed destination host, with optional user name.

             Constraints of the form `src-hostname>[user@]dst-hostname' allow a
             key available on a forwarded ssh-agent(1) to  be  used  through  a
             particular  host  (as specified by `src-hostname') to authenticate
             to a further host, specified by `dst-hostname'.

             Multiple destination constraints may be added when  loading  keys.
             When  attempting  authentication  with  a key that has destination
             constraints, the whole  connection  path,  including  ssh-agent(1)
             forwarding,  is tested against those constraints and each hop must
             be permitted for the attempt to succeed.  For example, if  key  is
             forwarded  to a remote host, `host-b', and is attempting authenti-
             cation to another host, `host-c', then the operation will be  suc-
             cessful  only  if  `host-b' was permitted from the origin host and
             the subsequent `host-b>host-c' hop is also permitted  by  destina-
             tion constraints.

             Hosts  are  identified  by their host keys, and are looked up from
             known hosts files by ssh-add.  Wildcards patterns may be used  for
             hostnames  and  certificate  host keys are supported.  By default,
             keys added by ssh-add are not destination constrained.

             Destination constraints were added in OpenSSH release  8.9.   Sup-
             port in both the remote SSH client and server is required when us-
             ing  destination-constrained  keys  over  a forwarded ssh-agent(1)
             channel.

             It is also important to note that destination constraints can only
             be enforced by ssh-agent(1) when a key is used, or when it is for-
             warded by a cooperating ssh(1).  Specifically, it does not prevent
             an attacker with access to a remote SSH_AUTH_SOCK from  forwarding
             it again and using it on a different host (but only to a permitted
             destination).

     -K      Load resident keys from a FIDO authenticator.

     -k      When  loading  keys  into or deleting keys from the agent, process
             plain private keys only and skip certificates.

     -L      Lists public key parameters of  all  identities  currently  repre-
             sented by the agent.

     -l      Lists  fingerprints of all identities currently represented by the
             agent.

     -N      When adding certificates, by default ssh-add will request that the
             agent automatically delete the certificate shortly after the  cer-
             tificate's  expiry  date.  This flag suppresses this behaviour and
             does not specify a lifetime for certificates added to an agent.

     -Q      Query the agent for the list of protocol extensions  it  supports.
             Note: not all agents support this query.

     -q      Be quiet after a successful operation.

     -S provider
             Specifies  a  path to a library that will be used when adding FIDO
             authenticator-hosted keys, overriding the default of using the in-
             ternal USB HID support.

     -s pkcs11
             Add keys provided by the PKCS#11 shared library pkcs11.   Certifi-
             cate files may optionally be listed as command-line arguments.  If
             these  are  present, then they will be loaded into the agent using
             any corresponding private keys loaded from the PKCS#11 token.

     -T pubkey ...
             Tests whether the private keys that correspond  to  the  specified
             pubkey  files  are usable by performing sign and verify operations
             on each.

     -t life
             Set a maximum lifetime when adding identities to  an  agent.   The
             lifetime may be specified in seconds or in a time format specified
             in sshd_config(5).

     -v      Verbose  mode.   Causes  ssh-add to print debugging messages about
             its progress.  This is helpful in debugging problems.  Multiple -v
             options increase the verbosity.  The maximum is 3.

     -X      Unlock the agent.

     -x      Lock the agent with a password.

ENVIRONMENT
     DISPLAY, SSH_ASKPASS and SSH_ASKPASS_REQUIRE
             If ssh-add needs a passphrase, it will read  the  passphrase  from
             the  current  terminal  if it was run from a terminal.  If ssh-add
             does not have a  terminal  associated  with  it  but  DISPLAY  and
             SSH_ASKPASS  are  set,  it  will  execute the program specified by
             SSH_ASKPASS (by default "ssh-askpass") and open an X11  window  to
             read  the  passphrase.   This  is particularly useful when calling
             ssh-add from a .xsession or related script.

             SSH_ASKPASS_REQUIRE allows further control  over  the  use  of  an
             askpass  program.  If this variable is set to "never" then ssh-add
             will never attempt to use one.  If it is  set  to  "prefer",  then
             ssh-add  will prefer to use the askpass program instead of the TTY
             when requesting passwords.  Finally, if the  variable  is  set  to
             "force",  then the askpass program will be used for all passphrase
             input regardless of whether DISPLAY is set.

     SSH_AUTH_SOCK
             Identifies the path of a Unix-domain socket  used  to  communicate
             with the agent.

     SSH_SK_PROVIDER
             Specifies  a  path to a library that will be used when loading any
             FIDO authenticator-hosted keys, overriding the  default  of  using
             the built-in USB HID support.

FILES
     ~/.ssh/id_ecdsa
     ~/.ssh/id_ecdsa_sk
     ~/.ssh/id_ed25519
     ~/.ssh/id_ed25519_sk
     ~/.ssh/id_rsa
             Contains the ECDSA, authenticator-hosted ECDSA, Ed25519, authenti-
             cator-hosted Ed25519 or RSA authentication identity of the user.

     Identity  files  should not be readable by anyone but the user.  Note that
     ssh-add ignores identity files if they are accessible by others.

EXIT STATUS
     Exit status is 0 on success, 1 if the specified command fails,  and  2  if
     ssh-add is unable to contact the authentication agent.

SEE ALSO
     ssh(1), ssh-agent(1), ssh-askpass(1), ssh-keygen(1), sshd(8)

AUTHORS
     OpenSSH  is  a  derivative  of the original and free ssh 1.2.12 release by
     Tatu Ylonen.  Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,  Theo
     de  Raadt and Dug Song removed many bugs, re-added newer features and cre-
     ated OpenSSH.  Markus Friedl contributed the support for SSH protocol ver-
     sions 1.5 and 2.0.

Debian                           March 5, 2026                       SSH-ADD(1)

ssh-agent

OpenSSH authentication agent

root@kali:~# ssh-agent -h
unknown option -- h
usage: ssh-agent [-c | -s] [-DdTU] [-a bind_address] [-E fingerprint_hash]
                 [-O option] [-P allowed_providers] [-t life]
       ssh-agent [-TU] [-a bind_address] [-E fingerprint_hash] [-O option]
                 [-P allowed_providers] [-t life] command [arg ...]
       ssh-agent [-c | -s] -k
       ssh-agent -u

ssh-argv0

Replaces the old ssh command-name as hostname handling

root@kali:~# man ssh-argv0
SSH-ARGV0(1)                 General Commands Manual               SSH-ARGV0(1)

NAME
     ssh-argv0 -- replaces the old ssh command-name as hostname handling

SYNOPSIS
     hostname | user@hostname [-l login_name] [command]

     hostname | user@hostname [-afgknqstvxACNTX1246] [-b bind_address]
     [-c cipher_spec] [-e escape_char] [-i identity_file] [-l login_name]
     [-m mac_spec] [-o option] [-p port] [-F configfile] [-L
     port:host:hostport] [-R port:host:hostport] [-D port] [command]

DESCRIPTION
     ssh-argv0  replaces the old ssh command-name as hostname handling.  If you
     link to this script with a hostname then executing the link is  equivalent
     to having executed ssh with that hostname as an argument.  All other argu-
     ments are passed to ssh and will be processed normally.

OPTIONS
     See ssh(1).

FILES
     See ssh(1).

AUTHORS
     OpenSSH  is  a  derivative  of the original and free ssh 1.2.12 release by
     Tatu Ylonen.  Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,  Theo
     de  Raadt and Dug Song removed many bugs, re-added newer features and cre-
     ated OpenSSH.  Markus Friedl contributed the support for SSH protocol ver-
     sions 1.5 and 2.0.  Natalie Amery wrote this ssh-argv0 script and the  as-
     sociated documentation.

SEE ALSO
     ssh(1)

Debian Project                 September 7, 2001                   SSH-ARGV0(1)

ssh-copy-id

Use locally available keys to authorise logins on a remote machine

root@kali:~# ssh-copy-id --help
Illegal option --
Usage: /usr/bin/ssh-copy-id [-h|-?|-f|-n|-s|-x] [-i [identity_file]] [-t target_path] [-F ssh_config] [[-o ssh_option] ...] [-p port] [user@]hostname
	-f: force mode -- copy keys without trying to check if they are already installed
	-n: dry run    -- no keys are actually copied
	-s: use sftp   -- use sftp instead of executing remote-commands. Can be useful if the remote only allows sftp
	-x: debug      -- enables -x in this shell, for debugging
	-h|-?: print this help

ssh-keygen

OpenSSH authentication key utility

root@kali:~# ssh-keygen --help
unknown option -- -
usage: ssh-keygen [-q] [-a rounds] [-b bits] [-C comment] [-f output_keyfile]
                  [-m format] [-N new_passphrase] [-O option]
                  [-t ecdsa | ecdsa-sk | ed25519 | ed25519-sk | rsa]
                  [-w provider] [-Z cipher]
       ssh-keygen -p [-a rounds] [-f keyfile] [-m format] [-N new_passphrase]
                   [-P old_passphrase] [-Z cipher]
       ssh-keygen -i [-f input_keyfile] [-m key_format]
       ssh-keygen -e [-f input_keyfile] [-m key_format]
       ssh-keygen -y [-f input_keyfile]
       ssh-keygen -c [-a rounds] [-C comment] [-f keyfile] [-P passphrase]
       ssh-keygen -l [-v] [-E fingerprint_hash] [-f input_keyfile]
       ssh-keygen -B [-f input_keyfile]
       ssh-keygen -D pkcs11
       ssh-keygen -F hostname [-lv] [-f known_hosts_file]
       ssh-keygen -H [-f known_hosts_file]
       ssh-keygen -K [-a rounds] [-w provider]
       ssh-keygen -R hostname [-f known_hosts_file]
       ssh-keygen -r hostname [-g] [-f input_keyfile]
       ssh-keygen -M generate [-O option] output_file
       ssh-keygen -M screen [-f input_file] [-O option] output_file
       ssh-keygen -I certificate_identity -s ca_key [-hU] [-D pkcs11_provider]
                  [-n principals] [-O option] [-V validity_interval]
                  [-z serial_number] file ...
       ssh-keygen -L [-f input_keyfile]
       ssh-keygen -A [-a rounds] [-f prefix_path]
       ssh-keygen -k -f krl_file [-u] [-s ca_public] [-z version_number]
                  file ...
       ssh-keygen -Q [-l] -f krl_file [file ...]
       ssh-keygen -Y find-principals -s signature_file -f allowed_signers_file
       ssh-keygen -Y match-principals -I signer_identity -f allowed_signers_file
       ssh-keygen -Y check-novalidate -n namespace -s signature_file
       ssh-keygen -Y sign -f key_file -n namespace file [-O option] ...
       ssh-keygen -Y verify -f allowed_signers_file -I signer_identity
                  -n namespace -s signature_file [-r krl_file] [-O option]

ssh-keyscan

Gather SSH public keys from servers

root@kali:~# ssh-keyscan -h
unknown option -- h
usage: ssh-keyscan [-46cDHqv] [-f file] [-O option] [-p port] [-T timeout]
                   [-t type] [host | addrlist namelist]

openssh-client-gssapi

Secure shell (SSH) client, with GSS-API support
This is the portable version of OpenSSH, a free implementation of the Secure Shell protocol as specified by the IETF secsh working group.

Ssh (Secure Shell) is a program for logging into a remote machine and for executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It can be used to provide applications with a secure communication channel.

This package provides versions of the ssh client and related programs built with support for GSS-API authentication and key exchange, which can be used with systems such as Kerberos. It is currently an empty package depending on openssh-client, but future releases will remove GSS-API support from openssh-client, so users who need it should install this package.

Installed size: 170 KB
How to install: sudo apt install openssh-client-gssapi

openssh-client-udeb

openssh-server

Secure shell (SSH) server, for secure access from remote machines
This is the portable version of OpenSSH, a free implementation of the Secure Shell protocol as specified by the IETF secsh working group.

Ssh (Secure Shell) is a program for logging into a remote machine and for executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It can be used to provide applications with a secure communication channel.

This package provides the sshd server.

In some countries it may be illegal to use any encryption at all without a special permit.

sshd replaces the insecure rshd program, which is obsolete for most purposes.

Installed size: 3.28 MB
How to install: sudo apt install openssh-server

sshd

OpenSSH daemon

root@kali:~# sshd -h
option requires an argument -- h
OpenSSH_10.3p1 Debian-4, OpenSSL 3.6.2 7 Apr 2026
usage: sshd [-46DdeGiqTtV] [-C connection_spec] [-c host_cert_file]
            [-E log_file] [-f config_file] [-g login_grace_time]
            [-h host_key_file] [-o option] [-p port] [-u len]

openssh-server-gssapi

Secure shell (SSH) server, with GSS-API key exchange
This is the portable version of OpenSSH, a free implementation of the Secure Shell protocol as specified by the IETF secsh working group.

Ssh (Secure Shell) is a program for logging into a remote machine and for executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It can be used to provide applications with a secure communication channel.

This package provides a version of the sshd server built with support for GSS-API authentication and key exchange, which can be used with systems such as Kerberos. It is currently an empty package depending on openssh-server, but future releases will remove GSS-API support from openssh-server, so users who need it should install this package.

Installed size: 170 KB
How to install: sudo apt install openssh-server-gssapi

openssh-server-udeb

openssh-sftp-server

Secure shell (SSH) sftp server module, for SFTP access from remote machines
This is the portable version of OpenSSH, a free implementation of the Secure Shell protocol as specified by the IETF secsh working group.

Ssh (Secure Shell) is a program for logging into a remote machine and for executing commands on a remote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP/IP ports can also be forwarded over the secure channel. It can be used to provide applications with a secure communication channel.

This package provides the SFTP server module for the SSH server. It is needed if you want to access your SSH server with SFTP. The SFTP server module also works with other SSH daemons like dropbear.

OpenSSH’s sftp and sftp-server implement revision 3 of the SSH filexfer protocol described in:

http://www.openssh.com/txt/draft-ietf-secsh-filexfer-02.txt

Newer versions of the draft will not be supported, though some features are individually implemented as extensions.

Installed size: 177 KB
How to install: sudo apt install openssh-sftp-server

openssh-tests

OpenSSH regression tests
This package provides OpenSSH’s regression test suite. It is mainly intended for use with the autopkgtest system, though can also be run directly using /usr/lib/openssh/regress/run-tests.

Installed size: 6.47 MB
How to install: sudo apt install openssh-tests

ssh

Secure shell client and server (metapackage)
This metapackage is a convenient way to install both the OpenSSH client and the OpenSSH server. It provides nothing in and of itself, so you may remove it if nothing depends on it.

Installed size: 170 KB
How to install: sudo apt install ssh

ssh-askpass-gnome

Interactive X program to prompt users for a passphrase for ssh-add
This has been split out of the main openssh-client package so that openssh-client does not need to depend on GTK+.

You probably want the ssh-askpass package instead, but this is provided to add to your choice and/or confusion.

Installed size: 207 KB
How to install: sudo apt install ssh-askpass-gnome