cis-gcp-cos-5.3.3

DevOps & Security

Ensure default group for the root account is GID 0

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5.3.3 Ensure default group for the root account is GID 0 (Automated)

Description

The usermod command can be used to specify which group the root user belongs to. This affects permissions of files that are created by the root user.

Rationale

Using GID 0 for the root account helps prevent root-owned files from accidentally becoming accessible to non-privileged users.

Audit Procedure

Run the following command and verify the result is 0:

# grep "^root:" /etc/passwd | cut -f4 -d:
0

Expected Result

The command should return 0, confirming that root's default group is GID 0.

Remediation

Run the following command to set the root user default group to GID 0:

# usermod -g 0 root

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	3.3 Configure Data Access Control Lists - Configure data access control lists based on a user's need to know. Apply data access control lists, also known as access permissions, to local and remote file systems, databases, and applications.	x	x	x
v7	5.1 Establish Secure Configurations - Maintain documented, standard security configuration standards for all authorized operating systems and software.	x	x	x

Profile

Level 1 - Server