SSH Audit
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ssh-audit is a tool for ssh server auditing.
Features
SSH1 and SSH2 protocol server support;
grab banner, recognize device or software and operating system, detect compression;
gather key-exchange, host-key, encryption and message authentication code algorithms;
output algorithm information (available since, removed/disabled, unsafe/weak/legacy, etc);
output algorithm recommendations (append or remove based on recognized software version);
output security information (related issues, assigned CVE list, etc);
analyze SSH version compatibility based on algorithm information;
historical information from OpenSSH, Dropbear SSH and libssh;
Source: https://github.com/arthepsy/ssh-audit Links: SSSH - Secure Secure SHell
running against a 3560 Switch
puffy201 ../ssh-audit# ./ssh-audit.py switch
# general
(gen) banner: SSH-2.0-Cisco-1.25
(gen) software: Cisco IOS/PIX sshd 1.25
(gen) compatibility: OpenSSH 3.9-6.6, Dropbear SSH 0.53+
(gen) compression: disabled
# key exchange algorithms
(kex) diffie-hellman-group-exchange-sha1 -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.3.0
(kex) diffie-hellman-group14-sha1 -- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 3.9, Dropbear SSH 0.53
(kex) diffie-hellman-group1-sha1 -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [fail] disabled (in client) since OpenSSH 7.0, logjam attack
`- [warn] using small 1024-bit modulus
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.3.0, Dropbear SSH 0.28
# host-key algorithms
(key) ssh-rsa -- [info] available since OpenSSH 2.5.0, Dropbear SSH 0.28
# encryption algorithms (ciphers)
(enc) aes128-cbc -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak cipher mode
`- [info] available since OpenSSH 2.3.0, Dropbear SSH 0.28
(enc) 3des-cbc -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak cipher
`- [warn] using weak cipher mode
`- [warn] using small 64-bit block size
`- [info] available since OpenSSH 1.2.2, Dropbear SSH 0.28
(enc) aes192-cbc -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak cipher mode
`- [info] available since OpenSSH 2.3.0
(enc) aes256-cbc -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak cipher mode
`- [info] available since OpenSSH 2.3.0, Dropbear SSH 0.47
# message authentication code algorithms
(mac) hmac-sha1 -- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.1.0, Dropbear SSH 0.28
(mac) hmac-sha1-96 -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] disabled (in client) since OpenSSH 7.2, legacy algorithm
`- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.5.0, Dropbear SSH 0.47
(mac) hmac-md5 -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] disabled (in client) since OpenSSH 7.2, legacy algorithm
`- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.1.0, Dropbear SSH 0.28
(mac) hmac-md5-96 -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] disabled (in client) since OpenSSH 7.2, legacy algorithm
`- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.5.0
# algorithm recommendations (for OpenSSH 3.9)
(rec) -diffie-hellman-group1-sha1 -- kex algorithm to remove
(rec) -diffie-hellman-group-exchange-sha1 -- kex algorithm to remove
(rec) -3des-cbc -- enc algorithm to remove
(rec) -aes128-cbc -- enc algorithm to remove
(rec) -aes192-cbc -- enc algorithm to remove
(rec) -aes256-cbc -- enc algorithm to remove
(rec) +aes128-ctr -- enc algorithm to append
(rec) +aes192-ctr -- enc algorithm to append
(rec) +aes256-ctr -- enc algorithm to append
(rec) -hmac-sha1-96 -- mac algorithm to remove
(rec) -hmac-md5 -- mac algorithm to remove
(rec) -hmac-md5-96 -- mac algorithm to remove
Running against OpenBSD Current
puffy201 ../ssh-audit# ./ssh-audit.py localhost
# general
(gen) banner: SSH-2.0-OpenSSH_8.2
(gen) software: OpenSSH 8.2
(gen) compatibility: OpenSSH 7.2+ (some functionality from 6.6), Dropbear SSH 2013.62+
(gen) compression: enabled (zlib@openssh.com)
# key exchange algorithms
(kex) diffie-hellman-group14-sha1 -- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 3.9, Dropbear SSH 0.53
# host-key algorithms
(key) rsa-sha2-512 -- [info] available since OpenSSH 7.2
(key) rsa-sha2-256 -- [info] available since OpenSSH 7.2
(key) ssh-rsa -- [info] available since OpenSSH 2.5.0, Dropbear SSH 0.28
(key) ecdsa-sha2-nistp256 -- [fail] using weak elliptic curves
`- [warn] using weak random number generator could reveal the key
`- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
(key) ssh-ed25519 -- [info] available since OpenSSH 6.5
# encryption algorithms (ciphers)
(enc) aes128-cbc -- [fail] removed (in server) since OpenSSH 6.7, unsafe algorithm
`- [warn] using weak cipher mode
`- [info] available since OpenSSH 2.3.0, Dropbear SSH 0.28
(enc) chacha20-poly1305@openssh.com -- [info] available since OpenSSH 6.5
`- [info] default cipher since OpenSSH 6.9.
(enc) aes128-ctr -- [info] available since OpenSSH 3.7, Dropbear SSH 0.52
(enc) aes192-ctr -- [info] available since OpenSSH 3.7
(enc) aes256-ctr -- [info] available since OpenSSH 3.7, Dropbear SSH 0.52
(enc) aes128-gcm@openssh.com -- [info] available since OpenSSH 6.2
(enc) aes256-gcm@openssh.com -- [info] available since OpenSSH 6.2
# message authentication code algorithms
(mac) umac-64-etm@openssh.com -- [warn] using small 64-bit tag size
`- [info] available since OpenSSH 6.2
(mac) umac-128-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha2-256-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha2-512-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha1-etm@openssh.com -- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 6.2
(mac) umac-64@openssh.com -- [warn] using encrypt-and-MAC mode
`- [warn] using small 64-bit tag size
`- [info] available since OpenSSH 4.7
(mac) umac-128@openssh.com -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 6.2
(mac) hmac-sha2-256 -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 5.9, Dropbear SSH 2013.56
(mac) hmac-sha2-512 -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 5.9, Dropbear SSH 2013.56
(mac) hmac-sha1 -- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.1.0, Dropbear SSH 0.28
# algorithm recommendations (for OpenSSH 8.2)
(rec) -diffie-hellman-group14-sha1 -- kex algorithm to remove
(rec) +diffie-hellman-group14-
Any Comments ?
sha256 -- kex algorithm to append
(rec) +diffie-hellman-group16-sha512 -- kex algorithm to append
(rec) +diffie-hellman-group18-sha512 -- kex algorithm to append
(rec) +curve25519-
Any Comments ?
sha256@libssh.org -- kex algorithm to append
(rec) -ecdsa-sha2-nistp256 -- key algorithm to remove
(rec) -aes128-cbc -- enc algorithm to remove
(rec) -hmac-sha1 -- mac algorithm to remove
(rec) -hmac-sha2-256 -- mac algorithm to remove
(rec) -hmac-sha2-512 -- mac algorithm to remove
(rec) -umac-64@openssh.com -- mac algorithm to remove
(rec) -umac-128@openssh.com -- mac algorithm to remove
(rec) -hmac-sha1-etm@openssh.com -- mac algorithm to remove
(rec) -umac-64-etm@openssh.com -- mac algorithm to remove
Running against OpenGear Console Server
puffy201 ../ssh-audit# ./ssh-audit.py 192.168.108.242
# general
(gen) banner: SSH-2.0-OpenSSH_7.7
(gen) software: OpenSSH 7.7
(gen) compatibility: OpenSSH 7.3+, Dropbear SSH 2016.73+
(gen) compression: enabled (zlib@openssh.com)
# key exchange algorithms
(kex) curve25519-
Any Comments ?
sha256 -- [warn] unknown algorithm
(kex) curve25519-
Any Comments ?
sha256@libssh.org -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
(kex) ecdh-sha2-nistp256 -- [fail] using weak elliptic curves
`- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
(kex) ecdh-sha2-nistp384 -- [fail] using weak elliptic curves
`- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
(kex) ecdh-sha2-nistp521 -- [fail] using weak elliptic curves
`- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
(kex) diffie-hellman-group-exchange-
Any Comments ?
sha256 -- [warn] using custom size modulus (possibly weak)
`- [info] available since OpenSSH 4.4
(kex) diffie-hellman-group16-sha512 -- [info] available since OpenSSH 7.3, Dropbear SSH 2016.73
(kex) diffie-hellman-group18-sha512 -- [info] available since OpenSSH 7.3
(kex) diffie-hellman-group14-
Any Comments ?
sha256 -- [info] available since OpenSSH 7.3, Dropbear SSH 2016.73
(kex) diffie-hellman-group14-sha1 -- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 3.9, Dropbear SSH 0.53
# host-key algorithms
(key) ssh-rsa -- [info] available since OpenSSH 2.5.0, Dropbear SSH 0.28
(key) rsa-sha2-512 -- [info] available since OpenSSH 7.2
(key) rsa-sha2-256 -- [info] available since OpenSSH 7.2
(key) ecdsa-sha2-nistp256 -- [fail] using weak elliptic curves
`- [warn] using weak random number generator could reveal the key
`- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
(key) ssh-ed25519 -- [info] available since OpenSSH 6.5
# encryption algorithms (ciphers)
(enc) chacha20-poly1305@openssh.com -- [info] available since OpenSSH 6.5
`- [info] default cipher since OpenSSH 6.9.
(enc) aes128-ctr -- [info] available since OpenSSH 3.7, Dropbear SSH 0.52
(enc) aes192-ctr -- [info] available since OpenSSH 3.7
(enc) aes256-ctr -- [info] available since OpenSSH 3.7, Dropbear SSH 0.52
(enc) aes128-gcm@openssh.com -- [info] available since OpenSSH 6.2
(enc) aes256-gcm@openssh.com -- [info] available since OpenSSH 6.2
# message authentication code algorithms
(mac) umac-64-etm@openssh.com -- [warn] using small 64-bit tag size
`- [info] available since OpenSSH 6.2
(mac) umac-128-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha2-256-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha2-512-etm@openssh.com -- [info] available since OpenSSH 6.2
(mac) hmac-sha1-etm@openssh.com -- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 6.2
(mac) umac-64@openssh.com -- [warn] using encrypt-and-MAC mode
`- [warn] using small 64-bit tag size
`- [info] available since OpenSSH 4.7
(mac) umac-128@openssh.com -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 6.2
(mac) hmac-sha2-256 -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 5.9, Dropbear SSH 2013.56
(mac) hmac-sha2-512 -- [warn] using encrypt-and-MAC mode
`- [info] available since OpenSSH 5.9, Dropbear SSH 2013.56
(mac) hmac-sha1 -- [warn] using encrypt-and-MAC mode
`- [warn] using weak hashing algorithm
`- [info] available since OpenSSH 2.1.0, Dropbear SSH 0.28
# algorithm recommendations (for OpenSSH 7.7)
(rec) -diffie-hellman-group14-sha1 -- kex algorithm to remove
(rec) -diffie-hellman-group-exchange-
Any Comments ?
sha256 -- kex algorithm to remove
(rec) -ecdh-sha2-nistp256 -- kex algorithm to remove
(rec) -ecdh-sha2-nistp384 -- kex algorithm to remove
(rec) -ecdh-sha2-nistp521 -- kex algorithm to remove
(rec) -ecdsa-sha2-nistp256 -- key algorithm to remove
(rec) -hmac-sha1 -- mac algorithm to remove
(rec) -hmac-sha2-256 -- mac algorithm to remove
(rec) -hmac-sha2-512 -- mac algorithm to remove
(rec) -umac-64@openssh.com -- mac algorithm to remove
(rec) -umac-128@openssh.com -- mac algorithm to remove
(rec) -hmac-sha1-etm@openssh.com -- mac algorithm to remove
(rec) -umac-64-etm@openssh.com -- mac algorithm to remove
Any Comments ?
sha256: fe854fc0309db2596eaca1b22f3644b721b89574cf44af563c42c488124069f6