What is Kubernetes security?

Kubernetes security encompasses the practices, tools, and configurations used to protect Kubernetes clusters, workloads, and data. It includes authentication, authorization (RBAC), network policies, pod security standards, secrets management, and runtime security.

What is the CKS certification?

The Certified Kubernetes Security Specialist (CKS) is a CNCF certification that validates expertise in securing Kubernetes clusters. It covers cluster setup and hardening, system hardening, minimizing microservice vulnerabilities, and supply chain security.

What are Kubernetes network policies?

Network policies are Kubernetes resources that control pod-to-pod and pod-to-external traffic. They act as a firewall for your cluster, allowing you to specify which pods can communicate with each other based on labels, namespaces, and ports.

What are Pod Security Standards?

Pod Security Standards (PSS) are predefined security profiles that define different levels of pod security restrictions: Privileged (unrestricted), Baseline (minimally restrictive to prevent known privilege escalations), and Restricted (heavily restricted following security best practices).

What is RBAC in Kubernetes?

Role-Based Access Control (RBAC) is a Kubernetes authorization mechanism that regulates access to resources based on user roles. It uses Role, ClusterRole, RoleBinding, and ClusterRoleBinding resources to define and assign permissions to users and service accounts.

How do I secure etcd in Kubernetes?

Secure etcd by enabling encryption at rest for secrets, using TLS for client-server communication, restricting access to etcd endpoints via firewall rules, enabling authentication, and running regular backups. etcd stores all cluster data including secrets.

What is a container escape attack?

A container escape attack occurs when a process breaks out of container isolation to access the host system or other containers. Common vectors include privileged containers, hostPath mounts, and kernel exploits. Mitigate with Pod Security Standards and seccomp profiles.

What tools are used for Kubernetes security scanning?

Popular Kubernetes security tools include Trivy (vulnerability scanning), Falco (runtime security), kube-bench (CIS benchmarks), OPA Gatekeeper and Kyverno (policy enforcement), Kubescape (security posture), and Cosign (image signing).

CVE-2022-47633 — Kyverno verifyImages bypass via malicious proxy/registry

HIGH8.1CVE-2022-47633GHSA-m3cq-xcx9-3gvm

CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected projects: kyverno
Disclosed: December 21, 2022
Last updated: April 27, 2026

Affected versions

Project	Vulnerable range
Kyverno	`>= 1.8.3, < 1.8.5`

Patched versions

Project	Fixed in
Kyverno	`1.8.5`

References

Summary

Users of Kyverno on versions 1.8.3 or 1.8.4 who use verifyImages rules to verify container image signatures, and do not prevent use of unknown registries, are affected.

Impact

A malicious proxy or registry can supply unsigned or attacker-controlled images that pass through verifyImages when the cluster permits arbitrary registry sources. Operators relying on verifyImages as their only image-trust gate could admit untrusted images, defeating the supply-chain control they thought was in place.

Detection

Audit cluster admission policies for an explicit allow-list of trusted registries. The absence of one — or the presence of broad wildcards — is the prerequisite. Inspect Kyverno policy reports for verifyImages decisions on images sourced from non-canonical registries.

Mitigation

Upgrade Kyverno to v1.8.5 or later.

Workaround: configure a Kyverno policy to restrict registries to a set of secure trusted image registries — see the upstream restrict-image-registries sample policy. Pair verifyImages with explicit registry pinning so a malicious proxy cannot interpose.

Affected versions

Patched versions

References

Summary​

Impact​

Detection​

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Summary

Impact

Detection

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