I have adapted my sshd_config file where I changed the value of:
- PasswordAuthentication no
- ChallengeResponseAuthentication no
- usePAM no ( now set to yes)
Furthermore I have restarted the sshd service by executing: sudo service ssh restart
. I have also done a reboot.
I am still allowed to login with a user password. Any idea what I have been missing?
# Package generated configuration file
# See the sshd_config(5) manpage for details
# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768
# Logging
SyslogFacility AUTH
LogLevel INFO
# Authentication:
LoginGraceTime 120
PermitRootLogin yes
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no
# Change to no to disable tunnelled clear text passwords
PasswordAuthentication no
# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
Subsystem sftp /usr/lib/openssh/sftp-server
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM no
EDIT:
PermitRootLogin
is now set tono
.usePAM
is now set toyes
.
Still not working though.
Best Answer
You need to do three things here:
(1) Set
PermitRootLogin
to bewithout-password
orrestrict-password
orno
. For security. I normally set it tono
.(2) You're missing something else that's pretty important. You should be using PAM for authentication for things -
UsePAM yes
is what the default usually is; this allows you to use UNIX user login data.(3) Also important, NORMALLY you set
ChallengeResponseAuthentication
tono
. This protects from bypassing thewithout-password
restriction forroot
logon. (The exception is if you're usinglibpam-duo
and the Duo Security 2FA system, in which case you needChallengeResponseAuthentication
set toyes
, but this isn't a typical setup.)Once you've done that,
sudo service ssh restart
to restart the SSH service with the new configuration. Attempt SSH from another window before you logout of your SSH session to make sure things are working as expected.