cis-gcp-cos-1.1.8

DevOps & Security

Ensure nodev option set on /var partition

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1.1.8 Ensure nodev option set on /var partition (Automated)

Description

The nodev mount option specifies that the filesystem cannot contain special devices.

Rationale

Since the /var filesystem is not intended to support devices, set this option to ensure that users cannot attempt to create block or character special devices in /var.

Audit Procedure

Verify that the nodev option is set if a /var partition exists. Run the following command and verify that nothing is returned:

# mount | grep -E '\s/var\s' | grep -v nodev

Expected Result

The command should return no output, confirming that the nodev option is set on the /var partition.

Remediation

Run the following command to remount /var:

# mount -o remount,nodev /var

Note: /etc is stateless on Container-Optimized OS. Therefore, /etc cannot be used to make these changes persistent across reboots. The steps mentioned above needs to be performed after every boot.

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 2 - Server | Automated