cis-k8s-v200-4-2-13

name	cis-k8s-v200-4.2.13
description	Ensure that a limit is set on pod PIDs (Manual)
category	cis-k8s
version	2.0.0
author	cyberstrike-official
tags	["cis","kubernetes","worker-node","kubelet","pod-pids","resource-limits"]
cis_id	4.2.13
cis_benchmark	CIS Kubernetes Benchmark v2.0.0
tech_stack	["kubernetes"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

4.2.13 Ensure that a limit is set on pod PIDs (Manual)

Profile Applicability

• Level 1 - Worker Node

Description

Ensure that the Kubelet sets limits on the number of PIDs that can be created by pods running on the node.

Rationale

By default pods running in a cluster can consume any number of PIDs, potentially exhausting the resources available on the node. Setting an appropriate limit reduces the risk of a denial of service attack on cluster nodes.

Impact

Setting this value will restrict the number of processes per pod. If this limit is lower than the number of PIDs required by a pod it will not operate.

Audit

Review the Kubelet's start-up parameters for the value of --pod-max-pids, and check the Kubelet configuration file for the PodPidsLimit. If neither of these values is set, then there is no limit in place.

Remediation

Decide on an appropriate level for this parameter and set it, either via the --pod-max-pids command line parameter or the PodPidsLimit configuration file setting.

Default Value

By default the number of PIDs is not limited.

References

1. https://kubernetes.io/docs/concepts/policy/pid-limiting/#pod-pid-limits

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	16.11 Leverage Vetted Modules or Services for Application Security Components - Leverage vetted modules or services for application security components, such as identity management, encryption, and auditing and logging. Using platform features in critical security functions will reduce developers' workload and minimize the likelihood of design or implementation errors. Modern operating systems provide effective mechanisms for identification, authentication, and authorization and make those mechanisms available to applications. Use only standardized, currently accepted, and extensively reviewed encryption algorithms. Operating systems also provide mechanisms to create and maintain secure audit logs.		*	*
v7	9.2 Ensure Only Approved Ports, Protocols and Services Are Running - Ensure that only network ports, protocols, and services listening on a system with validated business needs, are running on each system.		*	*