我的系统是 Ubuntu 18.04.5 LTS
当新用户在首次登录时被迫更改其初始密码时，密码更改机制无法正常工作。下面我展示了它现在如何工作的真实示例（我的评论在右侧）以及新密码最终的奇怪效果：
Password:
You are required to change your password immediately (root enforced)
Changing password for user123.
(current) UNIX password: (old password entered)
Enter new UNIX password: (new password typed - shorter than 14 characters)
Retype new UNIX password: (retyping password - shorter than 14 characters)
BAD PASSWORD: The password is shorter than 14 characters
New password: (typing again the same new password as above)
BAD PASSWORD: The password is shorter than 14 characters
New password: (still wrong, typing new 14 characters password)
Retype new password: (retyping new 14 characters password)
Password has been already used. Choose another.
Have exhausted maximum number of retries for service
此后，密码状态很奇怪 - 我无法登录我的旧密码（好的），但我也无法登录我的新 14 个字符的密码（原文如此！） - 相反，我可以登录少于 14 个字符的密码在上面的密码更改过程中说“BAD PASSWORD”。
我的 Ubuntu 上的密码更改过程出了什么问题？