Clair (tool)

Clair (tool)
Name	Clair
Developer	CoreOS / Red Hat / GitLab
Released	2015
Latest release	see project repositories
Programming language	Go
Operating system	Linux
License	Apache License 2.0
Genre	Vulnerability static analysis

Clair (tool)

Clair is an open-source static analysis tool for container vulnerability scanning developed initially by CoreOS and later maintained by Red Hat and contributors from projects such as GitLab and Quay. It analyzes container images and software artifacts to report known vulnerabilities using databases like the National Vulnerability Database and feeds from vendors including Debian, Ubuntu, Alpine Linux and Red Hat Enterprise Linux. Clair integrates with container registries, continuous integration systems like Jenkins, GitLab CI/CD and orchestration platforms such as Kubernetes and Docker Swarm.

Overview

Clair performs static analysis of application artifacts by inspecting filesystem contents of container images and comparing discovered packages against vulnerability databases maintained by organizations like the National Institute of Standards and Technology and vendors such as Canonical and Red Hat. It was introduced by CoreOS to secure container supply chains used by platforms including Kubernetes and OpenShift and has been incorporated into registry offerings like Quay and CI environments such as GitLab. Clair’s role is similar to other scanners from projects such as Anchore and companies like Aqua Security and Snyk.

Features

Clair offers layered image analysis, vulnerability metadata ingestion, and API-driven queries; these features align with practices used by registries like Quay and CI tools such as Jenkins and GitLab CI/CD. It detects vulnerabilities via Common Vulnerabilities and Exposures entries from sources like the National Vulnerability Database and vendor advisories from Debian Security and Red Hat Security. Other features include layered diffing for image updates, support for multiple package managers such as those in Debian, Alpine Linux, CentOS and Ubuntu, and structured output suitable for dashboards like those used by Grafana and Prometheus.

Architecture and Design

Clair is implemented in the Go (programming language) and designed as a stateless API service that stores analysis results in databases such as PostgreSQL. Its pipeline ingests vulnerability data from feeds and vendor advisories, matches packages within image layers, and produces vulnerability reports consumable by registry services like Quay and orchestrators such as Kubernetes. The architecture separates analyzer components, updater components, and an API front end to enable integration with systems like Docker Registry and platforms such as OpenShift. Scalability and observability are achieved through patterns familiar to operators of Prometheus instrumentation and Grafana dashboards.

Usage and Integration

Clair is typically deployed alongside container registries such as Quay or integrated into CI/CD pipelines using systems like Jenkins and GitLab CI/CD to scan images produced by build tools like Docker and Buildah. Common integrations include registry webhooks, image manifest retrieval from registries implementing the OCI specification and reporting to management consoles used by teams operating Kubernetes clusters or OpenShift installations. Operators combine Clair with orchestration and policy systems such as OPA (Open Policy Agent) and admission controllers in Kubernetes to enforce security gates during deployment.

Security and Vulnerability Scanning

Clair relies on vulnerability data from sources including the National Vulnerability Database, vendor advisories from Debian, Ubuntu, Red Hat, and distribution trackers for Alpine Linux and CentOS to map package versions to CVE identifiers. It performs static matching rather than dynamic analysis used by tools such as Falco; this allows fast scans suitable for registry-time checks performed by services like Quay and GitLab Container Registry. Limitations include dependence on upstream CVE metadata quality and package metadata formats used by ecosystems like APT and RPM, which influence detection accuracy for images built with builders like Docker and buildah.

Development and Community

Clair’s development began at CoreOS and continued with maintainers from Red Hat, GitLab, and the broader container security community including contributors from projects such as Quay and Kubernetes. The project accepts contributions via platforms like GitHub and engages with security researchers from organizations including Open Source Security Foundation and vendors like Canonical and Red Hat. Community activity includes issue tracking, pull requests, and integration work with projects such as Anchore and Snyk in ecosystem interoperability efforts.

License and Distribution

Clair is distributed under the Apache License 2.0 and is available through code hosting platforms such as GitHub and packaged by vendors for use with registries like Quay and platforms including OpenShift. Commercial offerings and managed services by companies such as Red Hat and GitLab may bundle Clair functionality or provide alternative scanning solutions with enterprise support.

Category:Security softwareCategory:Open-source software