cis-ubuntu2004-v300-3-2-2

name	cis-ubuntu2004-v300-3-2-2
description	Ensure tipc kernel module is not available
category	cis-networking
version	3.0.0
author	cyberstrike-official
tags	["cis","ubuntu","linux","ubuntu-20.04","kernel-module"]
cis_id	3.2.2
cis_benchmark	CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

3.2.2 Ensure tipc kernel module is not available (Automated)

Profile

• Level 2 - Server
• Level 2 - Workstation

Description

The Transparent Inter-Process Communication (TIPC) protocol is designed to provide communication between cluster nodes.

Rationale

• IF - the protocol is not being used, it is recommended that kernel module not be loaded, disabling the service to reduce the potential attack surface.

Impact

None expected if the TIPC protocol is not in use.

Audit Procedure

Command Line

Verify the tipc kernel module is not available on the system or has been disabled. This can be verified by performing the following or by running the audit script included below.

Run the following script to determine if the tipc kernel module is available on the system:

#!/usr/bin/env bash

{
  l_mod_name="tipc" l_mod_type="net"
  while IFS= read -r l_mod_path; do
      if [ -d "$l_mod_path/${l_mod_name//\-/\/}" ] && [ -n "$(ls -A "$l_mod_path/${l_mod_name//\-/\/}")" ]; then
          printf '%s\n' "$l_mod_name exists in $l_mod_path"
      fi
  done < <(readlink -f /usr/lib/modules/**/kernel/$l_mod_type || readlink -f
/lib/modules/**/kernel/$l_mod_type)
}

If nothing is returned, the tipc kernel module is not available on the system and no further audit steps are required. Note: Some systems may include the tipc filesystem as part of the kernel opposed to being available as a kernel module. In this case, the above audit will not return anything. This is also considered a passing state.

If anything is returned, verify the tipc kernel module is not loaded and not loadable by performing the following: