The root account must be the only account having a UID of 0.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-38500	RHEL-06-000032	SV-50301r2_rule		Medium

Description
An account has root authority if it has a UID of 0. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. Proper configuration of sudo is recommended to afford multiple system administrators access to root privileges in an accountable manner.

STIG	Date
Red Hat Enterprise Linux 6 Security Technical Implementation Guide	2015-05-26

Details

Check Text ( C-46057r2_chk )
To list all password file entries for accounts with UID 0, run the following command: # awk -F: '($3 == 0) {print}' /etc/passwd This should print only one line, for the user root. If any account other than root has a UID of 0, this is a finding.

Fix Text (F-43447r1_fix)
If any account other than root has a UID of 0, this misconfiguration should be investigated and the accounts other than root should be removed or have their UID changed.