Unlock another user by non-root account
 

Greetings.
I faced a problem which I need to resolve and I need your help, please.

We logged by non-root user, e.g. user A. We don't know root password and can't use sudo features. Another user, e.g. user B, locked in /etc/shadow. Don't have rights to edit or view /etc/shadow -> Permission denied when I try to do something with it.

Question: How can I unlock user B? Or what I need to find to do this
My friend said he found solution for a week ago, but don't tell it, just say it's look like a bug :(

I think by design regular users are not allowed to do that.

Exactly so. You must ask the system administrators to unlock the account. (Which also brings up the intriguing question of exactly why they locked it in the first place? Mmmm...?)