Cloud-Init should allow you to modify password after first time login. But if SSH closed while changing password:
WARNING: Your password has expired. You must change your password now and login again! Changing password for ubuntu. Current password: passwd: Authentication token manipulation error passwd: password unchanged Connection to 192.168.0.102 closed.
There might be Cloud-Init issue in older version.
There is a workaround to by-pass force passwd. Find /boot/firmware/user-data in the boot partition, then you will see options:
# On first boot, set the (default) ubuntu user's password to "ubuntu" and # expire user passwords chpasswd: expire: true list: - ubuntu:ubuntu
Update expire to false if you do not want to change password in first login. Or create your own username/password in list if expire is not work.
Please notice that device is not safe using default user name and password. Change it after you connect to the device.