Citation:
UsePAM Enables the Pluggable Authentication Module interface. If set to
"yes" this will enable PAM authentication using
ChallengeResponseAuthentication and PasswordAuthentication in
addition to PAM account and session module processing for all
authentication types.
Because PAM challenge-response authentication usually serves an
equivalent role to password authentication, you should disable
either PasswordAuthentication or ChallengeResponseAuthentication.
If UsePAM is enabled, you will not be able to run sshd(8) as a
non-root user. The default is "no".
Peux-tu mettre la directive UsePAM à no,redémarrer le service ssh et voir ce que ça donne?