ssh client disregards KbdInteractiveAuthentication option

[Søren Løvborg]

Even if keyboard-interactive authentication is disabled in .ssh/config or on the command-line, ssh(1) will go ahead and try it if supported by the server. (The client *does* respect PasswordAuthentication=no and PubkeyAuthentication=no.)

Using Ubuntu 13.10 Server 64-bit.

$ ssh -v -o KbdInteractiveAuthentication=no 127.0.0.1
OpenSSH_6.2p2 Ubuntu-6ubuntu0.1, OpenSSL 1.0.1e 11 Feb 2013
debug1: Reading configuration data /home/user/.ssh/config
debug1: /home/user/.ssh/config line 1: Applying options for 127.0.0.1
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to 127.0.0.1 [127.0.0.1] port 123.
debug1: Connection established.
debug1: identity file /home/user/.ssh/id_rsa type 1
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-4096
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-4096
debug1: identity file /home/user/.ssh/id_rsa-cert type -1
debug1: identity file /home/user/.ssh/id_dsa type -1
debug1: identity file /home/user/.ssh/id_dsa-cert type -1
debug1: identity file /home/user/.ssh/id_ecdsa type -1
debug1: identity file /home/user/.ssh/id_ecdsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2p2 Ubuntu-6ubuntu0.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.2p2 Ubuntu-6ubuntu0.1
debug1: match: OpenSSH_6.2p2 Ubuntu-6ubuntu0.1 pat OpenSSH*
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr <email address hidden> none
debug1: kex: client->server aes128-ctr <email address hidden> none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx
debug1: Host '[127.0.0.1]:123' is known and matches the ECDSA host key.
debug1: Found key in /home/user/.ssh/known_hosts:50
debug1: ssh_ecdsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: keyboard-interactive
debug1: Next authentication method: keyboard-interactive
Password:

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.