Passwd (command)

passwd USERNAME

passwd -l $USERNAME // for disabling password login

passwd -u $USERNAME // will unlock account if needed

passwd -u $USERNAME
passwd: password expiry information changed.

Busybox

passwd -u USERNAME
passwd: password for USERNAME changed by root

passwd -u USERNAME
passwd: password for USERNAME is already unlocked

journalctl 
Feb 05 14:35:55 SERVER_NAME passwd[29180]: pam_unix(passwd:chauthtok): password changed for root

Related terms

• PermitRootLogin in sshd_config
• PAM
• /etc/passwd (See also Zabbix /etc/passwd trigger)
• jailkit
• libpam_cracklib
• Passwordless sudo
• Lockout policy (Windows)
• Password policy
• openssl passwd
• /etc/systemd/logind.conf

Activities

• Read https://www.cyberciti.biz/faq/securing-passwords-libpam-cracklib-on-debian-ubuntu-linux/

See also

• Hardcoded password
• sudo, visudo, su, passwd, sudo su, Passwordless sudo, /etc/sudoers, /etc/sudoers.d/, /etc/sudoers, sudo --help
• OpenSSH (changelog): /etc/ssh/sshd_config | /etc/ssh/ssh_config | ~/.ssh/ | openSSL | sshd logs | sftp | scp | authorized_keys | ssh-keygen | ssh-keyscan | ssh-add | ssh-agent | ssh | Ssh -O stop | ssh-copy-id | CheckHostIP | UseKeychain, OpenSSF
• passwd, ssh-keygen, chage, /etc/passwd, Password policy, Passwd (package), mkpasswd, cracklib-check, Password cracking, Phone to sign in, Passkey, htpasswd