Cockpit 0.8 has been released:
This is a big milestone, in that we've moved beyond our prototype stage,
and closed up a bunch of security/stability issues.
In particular, we respect the system access privileges and don't provide
ways to escalate privileges without going through the usual channels
like polkit or sudo.
Because of this some features that used to work for accounts in the
wheel group, no only work as root. We're working on fixing this
regression by fixing system default policies in the various services
(like NetworkManager) that we access.
Our goal is that having Cockpit 0.8 or later installed should pose no
security risk. That said, you should still be careful when using it to
manage your system.