Clair vs Harbor

Clair is a free, Apache 2.0-licensed open-source service for static vulnerability analysis of OCI and Docker container images. It runs self-hosted on Linux and exposes an API: clients submit image manifests, Clair indexes their layers, scans image contents, and returns a persisted IndexReport. Analysis examines image contents rather than runtime behavior. Content-addressed OCI manifests and layers help avoid duplicate indexing. Clair continually ingests security data, while matcher requests provide current vulnerability analysis for an IndexReport; its notifier checks indexed manifests when new vulnerabilities appear and follows configured actions. The documented support matrix includes Ubuntu, Debian, RHEL, SUSE, Oracle, Alpine, AWS Linux, VMware Photon, and Python base containers. Clair v4 uses ClairCore as its analysis engine. Release 4.9.0 notes NVD 2.0 JSON feeds for CVSS enrichment and SPDX 2.3 encoding for index reports. The README lists a mailing list, IRC channel, and GitHub issues for community contact, and directs users to releases because the main branch may be unstable or broken. The listed plan is free.

Harbor is an open-source registry for managing artifacts across cloud-native platforms such as Kubernetes and Docker. It offers a web UI and extensible API, and can be installed on Kubernetes or a system with Docker support. Security features include policies, role-based access control, vulnerability scanning, and image signing and validation. Image scanning uses Trivy when enabled during installation, and Harbor can connect to additional scanners. It replicates images and charts to or from other registries in pull or push mode; listed adapters include Docker Hub, Amazon ECR, Google Container Registry, Azure Container Registry, and GitLab Registry. Authentication options are database, LDAP/Active Directory, and OIDC, though choosing database authentication and adding local users prevents a later switch to another mode. Project storage quotas are unlimited by default but can be set globally or per project. Robot account secrets are not stored by Harbor, so they must be saved when created; robot accounts cannot log into the user interface. Harbor is a CNCF Graduated project. HTTPS is recommended for production use.