In a Linux server I will have an user with gid=0 but it's uid won't be 0. As there are many commands with root:root and execute permissions for group I know there will be a lot of administrative task that this user can't do because many programs checks at start if UID=0
Anyone knows what commands/tasks can't do a user with UID!=0 and GUID=0? That user could mount filesystems or change passwords...?
For example, the user can't read messages as it has only read permissions for root owner. I know the question is open.