The complete guide to Kubernetes security tools

Kubernetes has become the go-to platform for running containerized applications, but it can come with serious security concerns that older tools can't handle. Organizations are getting hit with container security incidents regularly, and new clusters start getting attacked within minutes of going live on AWS or Azure, often before teams even finish setting them up.

This guide breaks down the Kubernetes security tooling landscape, what the tools are used for, and how to pick the right ones for your setup. We'll show you how different tools work together and help you build security that doesn't slow down your development teams.

What is a Kubernetes security tool?

Kubernetes security tools protect containerized workloads, infrastructure, and supply chains throughout the software lifecycle. These tools address security challenges that occur when traditional perimeter-based security (securing the network edge while trusting everything inside) breaks down in containerized environments.

Kubernetes security tools understand container orchestration—they handle ephemeral workloads, manage security across namespaces and clusters, integrate with Kubernetes role-based access control (RBAC) and network policies, and work within DevOps workflows.

Modern tools focus on preventing vulnerabilities from reaching production rather than detecting them after deployment—a shift from reactive to proactive security. Companies like Chainguard exemplify this with secure-by-default container images.

Common Kubernetes security threats and gaps

Since threats exist across multiple layers, Kubernetes environments face some unique security challenges. The biggest problem areas are:

Image and supply chain vulnerabilities: Container images rely heavily on third-party components with complex dependency chains, creating risks from supply chain attacks and incomplete visibility into what's actually running.

Misconfigurations and excessive permissions: Common issues include overly permissive RBAC policies, containers with unnecessary privileges, exposed API servers, and workloads without proper security contexts.

Runtime threats and limited visibility: Dynamic workloads that spin up and down rapidly make it difficult to detect container escapes, suspicious processes, or lateral movement between pods.

Types of Kubernetes security tools to consider

To achieve the best security posture, you’ll need a few different types of tools. We’ll cover different categories and provide some examples of each.

Container and image scanning tools

Container security and image scanning tools analyze container images to identify known vulnerabilities, usually by comparing software packages against known vulnerability databases like the National Vulnerability Database. These tools are inherently reactive because they can only detect already-known vulnerabilities, and require additional follow-up effort.

Trivy: Trivy is useful as a single, standardized scanning tool because it goes beyond basic CVE detection. It scans containers, filesystems, Git repositories, and Infrastructure as Code (IaC) templates.

Grype: Grype from Anchore focuses on container images and filesystems, using Syft-generated software bills of materials (SBOMs) to provide detailed vulnerability analysis. Its command-line interface (CLI)–first approach makes integrating into existing automation workflows and CD pipelines easy.

Clair: Clair was one of the first open source tools designed specifically for container image vulnerability scanning, originally developed by CoreOS before Red Hat's acquisition. With an API-first architecture and deep registry integration, it’s ideal for teams building custom scanning workflows or for those already using Quay for container management.

RapidFort: This tool combines vulnerability scanning with container optimization. It automatically removes unused software components to reduce the attack surface and image size, addressing vulnerabilities by elimination rather than detection.

Snyk: Snyk Container is part of a broader developer-focused security platform, specializing in Docker images and Kubernetes workloads with continuous monitoring capabilities. Its developer-centric approach provides contextual remediation advice and suggests specific base image upgrades.

Policy and admission control tools

Policy engines block risky configurations like unsigned images or privilege escalation attempts by integrating with Kubernetes admission controllers to enforce security rules during deployment. While these tools provide valuable preventive security, their effectiveness depends on well-defined policy configurations and a secure underlying supply chain. Compromised or unsigned images with missing provenance can still slip through if the underlying supply chain isn't secure, which is why it’s important to pair supply chain security platforms like Chainguard to provide verified, signed artifacts with your policy engines.

Here are some tools to consider:

Chainguard: While not a policy engine itself, Chainguard provides zero-CVE container images, signed SBOMs, and SLSA provenance that can be used with policy engines (like the ones listed below) to enforce that only verified, compliant workloads are admitted to Kubernetes clusters.

Open Policy Agent (OPA): OPA provides a flexible, general-purpose policy engine that allows organizations to write custom policies using the Rego language. OPA's functionality is both its strength and weakness. While it can handle just about any policy requirement, Rego is quite complex and requires significant expertise to implement and maintain.

Gatekeeper: Kubernetes’s native OPA wrapper provides policy enforcement through custom resource definitions (CRDs) that feel natural to Kubernetes operators. Gatekeeper simplifies OPA deployment and management while maintaining the same flexibility of the policy engine. It blocks problematic deployments, but unlike some other solutions, it doesn’t auto-fix the issues.

Kyverno: Kyverno offers a policy engine purpose-built for Kubernetes. Because it uses native YAML for policy definition, it’s more accessible to teams already familiar with Kubernetes manifests. Its mutation capabilities allow it to automate fixes for common configuration issues rather than just blocking deployments. Unlike OPA, it can’t enforce policies from non-Kubernetes systems like Terraform.

JSPolicy: Organizations with strong Node.js expertise may find benefit from using JSPolicy to write dynamic admission policies in JavaScript.

Runtime security and intrusion detection tools

Runtime security and intrusion detection tools monitor live Kubernetes workloads for threats like unexpected network activity or suspicious system calls. While valuable as a last line of defense, runtime security represents detection after potential compromise rather than prevention. Advanced tools can also detect differences between approved artifacts and what's actually running, identifying tampering or unauthorized changes.

Consider these runtime security options:

Falco: Falco is the de facto standard for open-source Kubernetes runtime security, using kernel-level monitoring to detect suspicious behavior in real time. It uses eBPF or syscall monitoring to track container runtime behavior and alert on policy violations, creating runtime protection without vendor lock-in. While not formally certified for compliance frameworks, Falco can enforce policies that map to NIST and FedRAMP controls.

Sysdig: Sysdig Secure builds upon the open-source Falco project, adding enterprise functionality like advanced alerting, compliance reporting, and forensic capabilities. This makes it attractive for larger organizations that need comprehensive runtime security with commercial support. It’s FedRAMP certified, so it meets government cloud requirements.

Tetragon: Tetragon from Cilium/Isovalent offers high-performance, eBPF-based security observability for cloud-native environments. It’s a good choice for teams already using Cilium networking, because the integration provides visibility into both the Kubernetes network and process behavior.

Configuration and benchmark testing tools

Configuration testing tools check Kubernetes clusters and manifests against security best practices and compliance frameworks, identifying issues like insecure defaults, overly permissive roles, or missing security contexts. Look for tools that support established benchmarks like CIS Kubernetes Benchmark, provide actionable remediation advice, and integrate easily into CI/CD pipelines for ongoing validation. Most teams use two or three of these together since they complement each other rather than overlap completely.

kube-bench: This tool from Aqua Security provides a straightforward CLI tool for checking Kubernetes clusters against CIS benchmarks. It's the gold standard for CIS compliance testing, focusing specifically on cluster-level security configurations like API server settings and node hardening rather than application workloads.

Kubescape: Kubescape offers end-to-end security scanning that tests clusters and YAML files against multiple compliance frameworks, including CIS benchmarks and NSA guidelines. It covers everything from pre-deployment manifest validation to runtime policy enforcement.

Kubesec: Kubesec evaluates pod specifications for security risks like missing security contexts or privilege escalation permissions. Its lightweight, API-driven approach is suited for quick security scores for individual pod configurations during development.

kubeaudit: This tool, developed by Spotify, provides open-source auditing capabilities that inspect Kubernetes resources for common security anti-patterns. With broad resource coverage, it audits everything from deployments to services, providing remediation recommendations.

Datree: Datree combines policy enforcement with misconfiguration prevention, validating Kubernetes manifests in CI pipelines before deployment. Its strength lies in custom policy creation and enforcement, acting as a policy gateway that prevents insecure configurations from reaching production.

Software supply chain security tools

Software supply chain security tools represent a growing category focused on securing what you build and deploy, rather than just monitoring how applications run in production. These tools make sure that the software components you rely on are verifiable, trusted, and free from tampering. They reduce upstream risk and ensure artifact integrity across the entire software development lifecycle. These tools work together; for example, Sigstore can sign the SBOMs generated by Syft, and then GUAC can analyze these signed artifacts.

Chainguard: Chainguard provides a comprehensive supply chain security platform beyond traditional scanning approaches. Chainguard offers zero-CVE container images and VMs with built-in SBOMs and cryptographic signatures. It’s built with SLSA 3 infrastructure and is FedRAMP compliant. Chainguard eliminates vulnerabilities at the source, rather than requiring reactive downstream remediation workflows.

Syft: This tool from Anchore generates detailed SBOMs that provide complete inventories of packages and components inside container images or filesystems. It detects packages across virtually every major language ecosystem, which may work well if you have a wide variety of packages.

Sigstore: Sigstore is a suite of open-source tools (cosign, fulcio, rekor) for signing, verifying, and logging container images and software artifacts using keyless signing and public transparency logs. To automate signing in your CI/CD pipelines, you'll typically need integration tools like GitHub Actions workflows, Tekton Chains, or custom scripts to call cosign during your build process.

GUAC (Graph for Understanding Artifact Composition): GUAC ingests security metadata from multiple sources to answer questions like "which of our services use this vulnerable library?" or "what's the blast radius if this container image is compromised?" It creates queryable graphs that let you trace dependencies and assess impact across your entire software portfolio. This is a specialized analysis platform for large organizations doing sophisticated supply chain analysis.

How to choose the right Kubernetes securityool

There's no one-size-fits-all security tool. Success depends on matching solutions to your specific risks, team capabilities, and existing workflows.

• Assess your biggest risks first: Focus on supply chain tools if you're worried about vulnerable dependencies, policy engines for misconfigurations, or runtime tools for active threat detection.

• Adapt your existing workflows: Choose tools that integrate with your current CI/CD pipelines, container registries, and kubectl processes without requiring major changes.

• Consider your team's expertise: Simple tools like kube-bench are great for getting started, while advanced solutions like OPA require dedicated security resources to implement effectively.

• Factor in total cost of ownership: Look beyond licensing to include training, maintenance, and productivity impact on development teams.

• Combine multiple tool categories: The most effective security strategies use scanning tools with policy enforcement and supply chain security rather than relying on a single solution.

• Prioritize prevention over detection: Tools that remove vulnerabilities at the source (like secure base images) are more generally cost-effective than managing extensive CVE backlogs after deployment. The most impactful tools eliminate vulnerabilities through daily updates and proactive remediation, while advanced approaches use secure-by-default components that prevent entire vulnerability classes before production.

• Integration with DevOps and CI/CD workflows: Look for solutions that integrate with existing CI/CD pipelines and container registries for automatic security, so it’s easy to get them up and running.

Why modern teams choose Chainguard

Companies like Snowflake, Anduril, Appian, and HP recognize that traditional scanning and patching can't keep up with how teams ship code today. Instead of chasing down thousands of CVEs after deployment, they use Chainguard's zero-CVE container images to eliminate vulnerabilities from the start.

Chainguard's container images are rebuilt daily with secure foundations and come with built-in SBOMs, signatures, and SLSA compliance. Teams regularly see massive reductions in vulnerabilities, faster compliance approvals, smaller CVE backlogs that free up engineering time, and smoother CI/CD pipelines without security bottlenecks.

Snowflake saw a dramatic drop in vulnerabilities by switching to Chainguard. When they adopted Chainguard Containers as part of their FedRAMP High compliance journey, they saw immediate results. "It's a remarkable thing when you introduce Chainguard Containers and see the vulnerability count plummet. Watching various applications go from hundreds or even thousands of vulnerabilities down to zero overnight is a really powerful testament to what Chainguard can do," says Brandon Sterne, Senior Manager of Product Security at Snowflake.

What does implementing Chainguard look like? Anduril's engineering manager, JP Ratliff, said it best: “It was probably one of the easiest integrations that we've ever done with third-party software. Basically, we just would drop in the Chainguard Container—rebuild the deployment, ship, test, ship. And that was it.”

Ready to move to proactive Kubernetes security? Talk to an expert at Chainguard to get started.