Tetragon

Tetragon is a free, open-source security observability and runtime enforcement tool for Linux, containers, and Kubernetes workloads. It uses eBPF to monitor activity and filter or enforce policies in the kernel in real time. Process monitoring can report executed binaries, command-line arguments, user IDs, parent processes, and start times. For Kubernetes, policies can filter by namespace, pod labels, and container fields; the tool supports containerd and CRI-O. Tetragon also monitors file access and changes, with the ability to block unauthorized file operations at the kernel level. It connects network events to processes and workloads and tracks socket events, connections, and data sent or received. Other monitoring covers process credential changes, kernel modules, and eBPF program activity. Insights are available in JSON logs and through a gRPC endpoint. Installation options include Helm on Kubernetes, Linux packages, and a container image. Its policy library pairs documented examples with use cases, while community examples are not curated for suitability or best practices.

Tetragon offers kernel-level monitoring and enforcement for teams managing Linux and Kubernetes environments. Its threat model and gRPC security guidance are important considerations for deployment.

Tetragon suits security teams monitoring Linux, container, and Kubernetes workloads, including process, file, privilege, and network activity. It is designed for self-hosted deployment.

Tetragon is a free, self-hosted runtime security tool for Linux, containers, and Kubernetes. It suits security teams that need workload-aware kernel visibility and immediate policy controls. Choose it for synchronous eBPF enforcement; look elsewhere if your threat model includes an attacker who already controls the host as root.

Overview

Tetragon monitors, filters, and enforces security policy synchronously in the kernel through eBPF. That makes it a runtime control rather than merely an event viewer: teams can inspect behavior and block prohibited activity as it occurs. Kubernetes-aware rules can target namespaces, pod labels, and container fields, preserving workload context across a busy cluster.

The project is a Cilium sub-project and a CNCF project. It is open source and self-hosted, with deployment choices for Kubernetes, Linux, and containers. A root-level host attacker remains outside its protection boundary because that attacker can disable or manipulate the local agent and its monitoring data.

Key features

Kernel runtime enforcement

Tetragon observes and filters kernel events and can enforce policy in real time. Synchronous enforcement is its clearest advantage over tools limited to retrospective alerting: a policy can stop an unauthorized operation instead of only recording it. The trade-off is operational responsibility for designing rules that block the right behavior without disrupting legitimate workloads.

Process, file, and privilege monitoring

Execution records include the binary, command-line arguments, user ID, parent process, and start time, giving investigators useful process lineage. File monitoring covers access and modifications and can block unauthorized file operations at the kernel level. Credential monitoring follows changes to user IDs, group IDs, and capabilities at system-call and kernel levels, making it relevant to teams watching privilege escalation and workload behavior.

Kubernetes and network context

Policies can filter by Kubernetes namespace, pod label, and container fields, with support for containerd and CRI-O. Network observability links events to processes and workloads and tracks socket lifecycles, connections, and bytes sent or received. This context is more actionable than isolated host events when security teams need to connect a connection or file change to a particular workload.

Host integrity and outputs

Tetragon monitors kernel-module loading and unloading, along with eBPF program loads and interactions. It exposes findings through JSON logs and a gRPC endpoint. The policy library pairs documented examples with use cases, while community examples are not curated as suitability or best-practice guidance, so teams should review them before production use.

Pricing

Tetragon: free. There is no paid plan or free trial. The free open-source offering includes the same self-hosted project and its Kubernetes, Linux, and container installation options; there are no seat or usage charges stated. Teams give up a vendor-priced hosted tier and must operate the deployment and policy lifecycle themselves.

Platforms

Tetragon supports API, Linux, and self-hosted deployments. Installation is documented through Helm on Kubernetes, released packages on Linux, and a container image, including an image from the Tetragon Quay repository. It is built for Linux, container, and Kubernetes workloads rather than as a general desktop security application.

Who it's for

Security teams responsible for Kubernetes workloads, container runtime behavior, process activity, privileges, files, and network connections are the best fit. It is particularly appropriate when kernel-level, workload-scoped enforcement matters and the organization can run its own agents and review policies. Teams seeking a managed service, broad endpoint coverage, or protection against a root-controlled host should choose another approach.

Pros and cons

Pros

• Synchronous kernel enforcement: policies can filter and block behavior in real time, not just generate alerts.
• Rich workload context: Kubernetes selectors and process-linked network events tie activity to namespaces, pods, containers, and processes.
• Broad runtime coverage: process, file, privilege, module, eBPF, socket, and byte-level network signals support investigations and controls.
• No license cost: the open-source plan is free and can be deployed on Kubernetes, Linux, or as a container.

Cons

• Self-hosting burden: teams must install, operate, and tune the agent and policies themselves.
• Root-level limitation: a root host attacker can disable or alter the agent and its monitoring data.
• gRPC exposure risk: a TCP listener without TLS client verification can allow network users to modify configuration; TLS and mutual TLS are supported.
• Uneven policy guidance: community examples are not curated for suitability or best practices.

Alternatives

Pick KubeArmor instead when you want another free, self-hosted API and Linux runtime-security project whose workload and platform support varies by its support matrix.

Falco is a free, open-source Linux and self-hosted option when zero-cost runtime monitoring is the priority.

Choose CloudSploit if you want a free self-hosted open-source version or are considering its separately priced hosted offering.

Fairwinds Polaris fits small teams seeking a free open-source policy engine across Linux, macOS, Windows, and web environments.

Consider KSPM Pro when a web service with a free tier for one Kubernetes cluster and real-time scans is preferable.

Kubescape is a free, Apache 2.0 self-hosted CLI and Kubernetes operator alternative.

Kyverno is another free Apache 2.0 open-source policy project for API, Linux, macOS, Windows, and self-hosted use.

Choose Monokle for a free MIT-licensed desktop tool on Linux, macOS, or Windows.

For broader category browsing, see Kubernetes Security Software, Cloud Workload Protection Platforms, Container Security Software, and eBPF Observability Tools.

Verdict

Tetragon is a strong choice for security teams that run Linux and Kubernetes themselves and need eBPF-backed, workload-aware enforcement at kernel speed. Its free license and detailed runtime context make it compelling for technically capable operators. Look elsewhere when you need managed operations or a control that remains trustworthy after a host attacker gains root.