From df8f238152283291bc6e54bc461b4166457bc6c9 Mon Sep 17 00:00:00 2001 From: Daniel Lenski Date: Fri, 28 Jun 2024 17:32:18 -0700 Subject: [PATCH 1/2] Include raw hostkey bytes in debug output --- src/ssh_audit/hostkeytest.py | 1 + 1 file changed, 1 insertion(+) diff --git a/src/ssh_audit/hostkeytest.py b/src/ssh_audit/hostkeytest.py index 094b2b7..b4dfe0b 100644 --- a/src/ssh_audit/hostkeytest.py +++ b/src/ssh_audit/hostkeytest.py @@ -157,6 +157,7 @@ class HostKeyTest: ca_key_type = kex_group.get_ca_type() ca_modulus_size = kex_group.get_ca_size() out.d("Hostkey type: [%s]; hostkey size: %u; CA type: [%s]; CA modulus size: %u" % (host_key_type, hostkey_modulus_size, ca_key_type, ca_modulus_size), write_now=True) + out.d("Raw hostkey bytes (%d): [%s]" % (len(raw_hostkey_bytes), raw_hostkey_bytes.hex()), write_now=True) # Record all the host key info. server_kex.set_host_key(host_key_type, raw_hostkey_bytes, hostkey_modulus_size, ca_key_type, ca_modulus_size) From 3361b176d57ed303c8281e4359a1a84b47a8ca54 Mon Sep 17 00:00:00 2001 From: Daniel Lenski Date: Fri, 28 Jun 2024 17:29:35 -0700 Subject: [PATCH 2/2] Recognize LANcom LCOS software and support extraction of ssh-ed448 key type LANcom router devices appear to be primarily used in Germany (see [1] for examples on the public Internet), and they appear to support the `ssh-ed448` key type which is documented in [2], but which has never been supported by any as-yet-released version of OpenSSH. [1] https://www.shodan.io/search?query=ssh+%22ed448%22 [2] https://datatracker.ietf.org/doc/html/rfc8709#name-public-key-format --- src/ssh_audit/hostkeytest.py | 3 +++ src/ssh_audit/kexdh.py | 3 +++ src/ssh_audit/software.py | 4 ++++ src/ssh_audit/ssh2_kexdb.py | 3 ++- 4 files changed, 12 insertions(+), 1 deletion(-) diff --git a/src/ssh_audit/hostkeytest.py b/src/ssh_audit/hostkeytest.py index b4dfe0b..2f91ac2 100644 --- a/src/ssh_audit/hostkeytest.py +++ b/src/ssh_audit/hostkeytest.py @@ -52,6 +52,9 @@ class HostKeyTest: 'ssh-ed25519': {'cert': False, 'variable_key_len': False}, 'ssh-ed25519-cert-v01@openssh.com': {'cert': True, 'variable_key_len': False}, + + 'ssh-ed448': {'cert': False, 'variable_key_len': False}, + # 'ssh-ed448-cert-v01@openssh.com': {'cert': True, 'variable_key_len': False}, } TWO2K_MODULUS_WARNING = '2048-bit modulus only provides 112-bits of symmetric strength' diff --git a/src/ssh_audit/kexdh.py b/src/ssh_audit/kexdh.py index 85beb8e..7335334 100644 --- a/src/ssh_audit/kexdh.py +++ b/src/ssh_audit/kexdh.py @@ -134,6 +134,9 @@ class KexDH: # pragma: nocover if self.__hostkey_type == 'ssh-ed25519': self.out.d("%s has a fixed host key modulus of 32." % self.__hostkey_type) self.__hostkey_n_len = 32 + elif self.__hostkey_type == 'ssh-ed448': + self.out.d("%s has a fixed host key modulus of 57." % self.__hostkey_type) + self.__hostkey_n_len = 57 else: # Here is the modulus size & actual modulus of the host key public key. hostkey_n, self.__hostkey_n_len, ptr = KexDH.__get_bytes(hostkey, ptr) diff --git a/src/ssh_audit/software.py b/src/ssh_audit/software.py index f13ebeb..21e22ca 100644 --- a/src/ssh_audit/software.py +++ b/src/ssh_audit/software.py @@ -224,4 +224,8 @@ class Software: mx = re.match(r'^PuTTY_Release_(.*)', software) if mx: return cls(None, Product.PuTTY, mx.group(1), None, None) + mx = re.match(r'^lancom(.*)', software) + if mx: + v, p = 'LANcom', 'LCOS sshd' + return cls(v, p, mx.group(1), None, None) return None diff --git a/src/ssh_audit/ssh2_kexdb.py b/src/ssh_audit/ssh2_kexdb.py index f65e014..e5841df 100644 --- a/src/ssh_audit/ssh2_kexdb.py +++ b/src/ssh_audit/ssh2_kexdb.py @@ -68,6 +68,7 @@ class SSH2_KexDB: # pylint: disable=too-few-public-methods INFO_DEPRECATED_IN_OPENSSH88 = 'deprecated in OpenSSH 8.8: https://www.openssh.com/txt/release-8.8' INFO_DISABLED_IN_DBEAR67 = 'disabled in Dropbear SSH 2015.67' INFO_DISABLED_IN_OPENSSH70 = 'disabled in OpenSSH 7.0: https://www.openssh.com/txt/release-7.0' + INFO_RFC8709_NOT_OPENSSH = 'described in RFC8709 but never implemented in OpenSSH' INFO_NEVER_IMPLEMENTED_IN_OPENSSH = 'despite the @openssh.com tag, this was never implemented in OpenSSH' INFO_REMOVED_IN_OPENSSH61 = 'removed since OpenSSH 6.1, removed from specification' INFO_REMOVED_IN_OPENSSH69 = 'removed in OpenSSH 6.9: https://www.openssh.com/txt/release-6.9' @@ -245,7 +246,7 @@ class SSH2_KexDB: # pylint: disable=too-few-public-methods 'ssh-dss-sha512@ssh.com': [[], [FAIL_1024BIT_MODULUS]], 'ssh-ed25519': [['6.5,d2020.79,l10.7.0']], 'ssh-ed25519-cert-v01@openssh.com': [['6.5']], - 'ssh-ed448': [[]], + 'ssh-ed448': [[], [], [], [INFO_RFC8709_NOT_OPENSSH]], 'ssh-ed448-cert-v01@openssh.com': [[], [], [], [INFO_NEVER_IMPLEMENTED_IN_OPENSSH]], 'ssh-gost2001': [[], [FAIL_UNTRUSTED]], 'ssh-gost2012-256': [[], [FAIL_UNTRUSTED]],