How to change the password if the shadow file has "!!"?

Question

[root@notebook ~]# grep USER /etc/shadow
USER:!!:16577:1:90:7:::
[root@notebook ~]# 
[root@notebook ~]# su - USER
[USER@notebook ~]$ id
uid=1000(USER) gid=983(GROUPN) groups=983(GROUPN),10(wheel) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
[USER@notebook ~]$ passwd
Changing password for user USER.
Changing password for USER.
(current) UNIX password: 
passwd: Authentication token manipulation error
[USER@notebook ~]$ 

Question: I am a normal user on a RHEL machine. How can I change my password without root permission?

When it asks for current pw at pw change, I just hit ENTER, because there is no password set, see the "!!".

Answer 1

You cannot, at least you must have sudo access or USER must have sudo privilege.

Answer 2

The problem in this case is, there isn't a valid password to specify as the existing one. The passwd command allows root to change passwords of other users without entering the original password. You can modify sudoers (as root of course) to allow this user to change the password for that user:

USER ALL = (root) NOPASSWD: /usr/bin/passwd USER

There is at least one weakness to this approach: the user can override system safeguards against poor, stupid passwords.