In Kubernetes, manifests are declarative configuration files that describe the state you want for workloads and cluster resources. They typically define objects such as Pods, Deployments, Services, volumes, and network policies, along with settings like image names, resource limits, and access rules. Kubernetes then reconciles the live environment to match those definitions.
Manifests matter in cyber security because they control how applications are deployed, exposed, and isolated. A small error can create an overly permissive service, mount sensitive data incorrectly, or expose a workload to the internet. Attackers may also target manifests in source control or CI/CD pipelines to slip in backdoors, privilege changes, or malicious images. Defenders reduce risk by reviewing changes, enforcing least privilege, scanning manifests for unsafe settings, and validating them in staging before production rollout.