KubeArmor

Overview

KubeArmor is a free, open-source runtime security system for restricting activity in workloads and hosts. It suits teams that operate Linux-based infrastructure and want policies tied to Kubernetes workloads as well as other supported environments. Its appeal is meaningful runtime enforcement without a software charge; its chief caveat is that both enforcement and platform coverage depend on the environment.

Key features

KubeArmor applies runtime rules through Linux Security Modules, including AppArmor, SELinux, and BPF-LSM. Container policies can allow, audit, or block actions, with Block as the default. Rules can target process and file paths, network protocols, capabilities, and system calls. This breadth gives security teams several ways to constrain workload behavior, but system-call monitoring is audit-only, so it provides visibility rather than prevention for that activity.

Kubernetes policy authors can use metadata and select pods by labels or label expressions, making it possible to target workloads by identity. eBPF-based telemetry records policy violations and tracks container processes with container, pod, and namespace identities. Hardening guidance draws on MITRE, STIG, and CIS, while integrations include OpenTelemetry, Prometheus, Kafka, Grafana, ELK dashboards, a GitHub Action, and a Rancher UI extension.

Deployment coverage spans Kubernetes, non-Kubernetes containers, virtual machines, and bare-metal hosts. The support matrix includes environments such as GKE, AKS, OKE, IKS, EKS, OpenShift, Rancher, DigitalOcean, and Alibaba Cloud, but the usable combination depends on operating system, architecture, and enforcement mode. Some RHEL or CentOS 8.4-and-earlier Kubernetes configurations and Oracle Ampere are observability-only; VMware Tanzu entries are under construction. Treat the matrix as a prerequisite to adoption, particularly if blocking enforcement is required.

Pricing

KubeArmor is open source and free: its KubeArmor plan costs nothing. There are no paid tiers or seat and quota terms in this plan. The trade-off is operational rather than financial: teams deploy and manage the self-hosted project, and workload and platform support varies. Kubernetes installation uses Helm and kubectl, including Helm commands to add the chart repository and install the Operator.

Platforms

The listed platforms are API, Linux, and self-hosted deployment. The wider workload matrix covers Kubernetes, other containers, virtual machines, and bare-metal hosts. Admission control is not included, so KubeArmor is a runtime control rather than an admission-control option.

Who it's for

KubeArmor is a strong fit for infrastructure and security teams that can operate self-hosted Linux security controls and need runtime policies for cloud containers, IoT and edge workloads, or 5G networks. Community governance and CNCF Sandbox status, alongside maintainer email, CNCF Slack, GitHub Discussions, and GitHub Issues, give users channels for project questions. Security vulnerabilities should go through the project's security process, not public GitHub issues.

It is a weaker fit for teams seeking admission control, guaranteed blocking support across every environment, or a managed service. Teams must also be prepared to validate OS, architecture, and enforcement compatibility before relying on policies to prevent activity.

Pros and cons

• Pros: Free and open source, with runtime rules for processes, files, network operations, capabilities, and system calls.
• Pros: Kubernetes policies can target pods through labels and metadata, while telemetry associates events with workload identities.
• Pros: Deployment coverage reaches beyond Kubernetes to containers, virtual machines, and bare-metal hosts.
• Cons: System-call monitoring is audit-only, which limits prevention for that policy scope.
• Cons: Support depends on platform and enforcement mode; some configurations are observability-only, and Tanzu support remains under construction.
• Cons: Self-hosted deployment places installation and operational responsibility on the user, and there is no admission control.

Alternatives

Tetragon is another free, open-source option for readers comparing Linux, Kubernetes, and container security projects. Falco is a free, open-source Linux and self-hosted alternative. Tracee is a free Linux-only open-source choice, with compatible-kernel and elevated-capability requirements.

Calico Cloud is worth considering for teams wanting a freemium option with a free tier limited to one user and one cluster, 24-hour log retention, and a view-only Policy Editor. Amazon GuardDuty suits readers considering a paid, pay-as-you-go service whose charges vary by analyzed data and AWS Region. Qualys TotalCloud offers a free license with limited API calls for control evaluation, with its cloud platform subscription priced according to the platform.

Bitdefender Total Security is a paid alternative aimed at a different device mix, with an individual plan covering five devices and one account. CrowdStrike Falcon Surface is another paid option for readers who prefer to request a demo rather than choose a published-price plan. For broader comparisons, see Cloud Workload Protection Platforms, Kubernetes Security Software, and Container Security Software.

Verdict

Choose KubeArmor if you need a free, self-hosted runtime policy system and can align its Linux enforcement options with your workload platforms. Its strongest reason to choose is the combination of workload-aware Kubernetes rules and controls across several workload types. Look elsewhere if you need admission control, system-call blocking, or consistent enforcement on an environment the support matrix limits.