Container Security Tools: A buyer’s guide

Containerized applications and cloud-native infrastructure have become foundational to modern software development, but securing them is hard and only getting harder. High-profile software supply chain breaches, ranging from SolarWinds in 2020 to XZ Utils in 2024, have exposed how vulnerable our build and deployment pipelines can be.

Meanwhile, the number of container-related vulnerabilities has spiked. Research by Netrise shows that the average container has over 600 known vulnerabilities in its underlying components. Over 45% of these vulnerabilities are 2–10+ years old.

Security and development times face a mounting backlog of CVEs. In our research, 7% of the 230 popular Bitnami container images we scanned contained CVEs listed in VulnCheck’s Known Exploited Vulnerability (KEV) catalog; each CVE took about three hours to triage.

Let’s talk about container security tools: how they work, how they’re categorized, and the features to compare.

What are container security tools?

Container security tools are designed to protect containerized applications and the infrastructure they run on, across every stage of the container lifecycle, from image build and registry storage to deployment, runtime, and decommissioning.

Unlike traditional security tools, container security tools are purpose-built for the unique attributes of containers, including layered image composition, rapid deployment, orchestration via platforms like Kubernetes, and ephemeral runtime behavior. These tools typically address a range of needs common across containers, including:

• Vulnerability management: Scanning container images and the packages and dependencies within them for known vulnerabilities, including open-source components, and helping teams prioritize and remediate those risks

• Configuration and policy enforcement: Validating container build configurations, Kubernetes manifest settings, network policies, access controls, etc., against a defined set of rules to adhere to security best practices or compliance requirements

• Runtime defense and monitoring: Continuously monitoring running containers and the host and cluster around them for anomalous or malicious behavior, a last line of defense to supplement hardened containers and build-time tooling

• Supply chain security and provenance: Generating software bills of materials (SBOMs) to inventory components, signing artifacts, and using cryptographic attestations to ensure each image comes from a trusted build process, and checking for tampering or unvetted dependencies

• Compliance reporting and audit support: Producing audit logs of policy checks, showing that images have been scanned and signed, or mapping security controls to frameworks like FedRAMP, among other functions, to support compliance

Modern container security emphasizes preventative controls, such as cutting off vulnerabilities and misconfigurations at the source, so most issues never make it to production. The goal is to apply checks in development and build phases, use secure base images, and enforce immutability, so containers are hardened before they run.

Types of container security tools

Teams typically rely on a mix of scanners, policy engines, runtime monitors, and hardening solutions, each covering different facets of the container risk landscape.

Image scanners and vulnerability detectors

Image scanning and vulnerability detection tools look for known security issues in container images, and sometimes the file systems or packages within running containers. Typically, these tools compare the contents of the image (including OS packages, libraries, and language dependencies) against vulnerability databases.

A well-known challenge with image scanning is the often overwhelming amount of scanner noise and the false positives these scans often produce. Because container images frequently bundle entire operating systems' worth of packages, a scanner may report dozens or hundreds of findings per image, even though many are not truly exploitable or relevant.

Despite the noise issue, vulnerability scanners are critical to container security. Some leading image scanning tools in 2025 include:

• Trivy: An open-source scanner by Aqua Security that scans container images, file systems, and Git repos for vulnerabilities, and also does configuration lints. It offers comprehensive scanning with a single binary and minimal setup, which is why many devs integrate it into their CIs.

• Grype: An open-source scanner by Anchore for scanning images and filesystems. Grype is often used to scan SBOMs created by Syft, Anchore’s SBOM generator.

• Clair: An open-source project originally by CoreOS (now part of the CNCF) that provides static image scanning. Clair maintains a database of vulnerabilities and allows you to push images or layers to it for analysis.

• Dockle: An open-source tool for container image linting. Rather than looking for CVEs, Docklet checks for security best practices in the image (e.g., no plaintext credentials and avoiding root users).

• RapidFort: A commercial tool that automatically minimizes container images. It analyzes an application’s runtime to determine which libraries and files are actually used, and then strips out unused components from the image.

When evaluating image scanners, you’ll want to check what packages and dependencies they can scan, how they integrate with other systems, how well they perform, and the quality of the vulnerability data they produce (including false positive rates).

Policy and compliance enforcement

These tools automatically enforce security policies and check compliance before deployment, especially during the container build and deployment phases. They validate container images, Kubernetes configurations, and infrastructure against encoded rules based on industry benchmarks or your own policies.

Some leading policy and compliance tools include:

• Open Policy Agent (OPA): A general-purpose policy engine that isn’t container-specific but can be deployed with Gatekeeper in Kubernetes to enforce policies on cluster resources.

• Kyverno: A policy engine designed specifically for Kubernetes, using familiar Kubernetes CRDs and YAML syntax for defining rules. It can mutate configurations, validate them, and generate default resources.

• Datree: An open-source tool focused on policy compliance for Kubernetes configurations and cluster resources. It comes with predefined rules and plugs into CI or kubectl to evaluate manifests before they’re applied.

Validation, like security, is increasingly shifting left; the pressure to secure configurations at scale means you likely need tooling that can support validation early.

Runtime threat detection and monitoring

Runtime threat detection tools monitor running containers and their host systems for indicators of compromise or abnormal behavior. They look for signs like unexpected processes within a container, suspicious system calls, signs of container escape attempts, unusual network connections, or known malware signatures.

Note that runtime threat detection is complementary to build-time prevention, not a replacement. It catches things that preventive controls might miss, such as a new zero-day exploit that gets executed within a container or a malicious insider abusing legitimate tools. Relying solely on runtime detection is dangerous because once an alert fires, the attack may already be in progress.

Some tools in this category include:

• Falco: An open-source container threat detection engine with a set of rules out of the box for common container/K8s threats, which you can complement with your own.

• Tracee: An open-source tool by Aqua, based on eBPF (extended Berkeley Packet Filter) that provides a library of detectors for suspicious behavior, such as processes with strange privilege escalations and known kernel exploit patterns.

• Tetragon: An open-source tool by Isovalent that can detect and enforce policies at the kernel level using eBPF.

• Sysdig Secure: A commercial tool with runtime threat detection and features for automatically shutting down offending containers or pausing them for forensic capture.

As you examine runtime threat detection and monitoring tools, look for features that include behavioral monitoring informed by container context, learning normal behavior for your containers, and alerting on deviations.

Secrets and credential protection

These tools help manage and protect secrets, such as passwords, API keys, tokens, and certificates, in the context of containerized applications. A single leaked credential can undermine all other security measures, so managing secrets properly is a foundational aspect of container security.

Some leading policy and compliance tools are:

• HashiCorp Vault: An open-source secrets manager that supports many secret engines (including AWS keys, DB credentials, and PKI) and has a robust access control policy framework, providing features like dynamic secrets and leasing.

• Doppler: A hosted secrets management service with a unified dashboard and CLI to manage secrets across environments and inject them into your apps.

• SOPS: An open-source tool for keeping encrypted secrets in source control. SOPS encrypts fields in YAML/JSON documents using keys from KMS or PGP, so you can safely store the file in e.g., a git repo.

• GitHub Advanced Security: If your code is on GitHub, their secret scanning will alert you almost immediately if any of hundreds of types of secrets get committed.

• TruffleHog: A tool that scans code repositories for high-entropy strings and exposed credentials.

Development teams looking to secure their secrets should use a combination of preventive and detective controls.

Infrastructure and host hardening

These tools focus on securing the environment that your containers run on, including Kubernetes nodes, container host OS, underlying VMs, and the kernel. Containers share the host OS kernel, so if the host is insecure, containers are at risk, too, whether in the cloud or on-prem. They can be especially helpful in highly regulated environments, where host hardening can remove or reduce attackers’ entry points and opportunities for misconfiguration.

Some leading policy and compliance tools include:

• Chainguard VMs: Chainguard’s VM images are optimized for running container workloads. As minimal distros, often built from scratch using their Chainguard OS base, they come with secure defaults and zero known vulnerabilities. A Chainguard-secured VM image can immediately eliminate a large swath of OS-level CVEs when swapped for a base one.

• Bottlerocket: An open-source Linux OS by AWS for container hosts. It’s used for EKS (AWS’s Kubernetes) as an option for worker nodes.

• Flatcar Container Linux: A minimal, auto-updating Linux distro designed for containers with automated updates and only the necessary components for running containers.

• Talos OS: A secure-by-default tool built for Kubernetes with built-in hardening features.

A hardened container host OS can eliminate dozens of known CVEs and misconfigurations you’d otherwise have to find and fix. Being secure by default also simplifies compliance and tool sprawl.

Software supply chain security solutions

Software supply chain security tools focus on the security of the processes and artifacts that form your applications, such as code, dependencies, build systems, container images, and deployments. Their services include verifying who built your container images and how, tracing components via SBOMs, and digitally signing materials to catch any tampering.

By the end of 2025, Gartner predicts that 45% of organizations will have experienced a supply chain attack. Check out our buyer’s guide on supply chain security to see which tools fit your use case best.

How to choose the right container security tools

Not all tools are created equal, and choosing the right one means balancing feature depth with real-world usability. Focus on the capabilities that most impact your security outcomes, as well as the tool’s fit for your team and environment.

• Vulnerability scanning and prioritization: How comprehensive is the scan coverage? Can the tool reduce noise through exploitability analysis, runtime context, or risk scoring?

• SBOM and provenance support: Can it generate and manage SBOMs to track where and how images were built? Strong provenance features improve transparency and trust across your software supply chain.

• Policy and compliance alignment: Does it support your compliance needs with pre-made rules or flexible policy engines? Look for options that log policy checks, generate compliance reports, and map controls to frameworks.

• CI/CD and registry integration: How well does it fit into your existing pipelines, registries, and developer tools? Tools that block deploys or suggest fixes within CI can shift security left without slowing you down.

• Context and signal quality: Can it prioritize findings based on runtime behavior or usage? Tools that combine context awareness with high signal-to-noise help surface real risks and avoid alert fatigue.

• Lifecycle coverage and integration: Does it span build to runtime, or will you need multiple tools? Either way, check how well it integrates with other tools to avoid gaps or duplication.

• Developer experience: Is it fast, intuitive, and compatible with your developers' workflow? If not, developers may find ways to avoid or ignore them.

• Patching and maintenance burden: Does it just detect issues or help resolve them? Tools that minimize image size, auto-patch, or provide maintained components reduce long-term risk and overhead.

Overall, focus on fit, effectiveness, and future-proofing. The right container security tool is one that fits your team’s workflow, effectively addresses the threats you care about (with high signal, low noise), and will remain useful as your environment and compliance needs grow.

Eliminate CVEs for good with Chainguard

Securing containerized applications doesn’t have to be reactive and stressful.

By focusing on preventative measures, you can build a robust and sustainable security approach. Many tools help manage container security, whereas only a select few help solve or avoid issues.

Chainguard is a secure-by-default platform offering hardened container images, curated libraries, and infrastructure-level protection. With Chainguard, you can tame the complexity, cut the noise, meet your compliance goals, and secure your containers without slowing delivery.

Curious about how security can be default, rather than just an add-on? Talk to an expert to learn more.