GitLab Documentation

Static Application Security Testing for Docker containers with GitLab CI/CD

Static Application Security Testing for Docker containers with GitLab CI/CD

You can check your Docker images (or more precisely the containers) for known vulnerabilities by using Clair and clair-scanner, two open source tools for Vulnerability Static Analysis for containers.

All you need is a GitLab Runner with the Docker executor (the shared Runners on GitLab.com will work fine). You can then add a new job to .gitlab-ci.yml, called sast:container:

sast:container:
  image: docker:latest
  variables:
    DOCKER_DRIVER: overlay2
    ## Define two new variables based on GitLab's CI/CD predefined variables
    ## https://docs.gitlab.com/ee/ci/variables/#predefined-variables-environment-variables
    CI_APPLICATION_REPOSITORY: $CI_REGISTRY_IMAGE/$CI_COMMIT_REF_SLUG
    CI_APPLICATION_TAG: $CI_COMMIT_SHA
  allow_failure: true
  services:
    - docker:dind
  script:
    - docker run -d --name db arminc/clair-db:latest
    - docker run -p 6060:6060 --link db:postgres -d --name clair arminc/clair-local-scan:v2.0.1
    - apk add -U wget ca-certificates
    - docker pull ${CI_APPLICATION_REPOSITORY}:${CI_APPLICATION_TAG}
    - wget https://github.com/arminc/clair-scanner/releases/download/v8/clair-scanner_linux_amd64
    - mv clair-scanner_linux_amd64 clair-scanner
    - chmod +x clair-scanner
    - touch clair-whitelist.yml
    - ./clair-scanner -c http://docker:6060 --ip $(hostname -i) -r gl-sast-container-report.json -l clair.log -w clair-whitelist.yml ${CI_APPLICATION_REPOSITORY}:${CI_APPLICATION_TAG} || true
  artifacts:
    paths: [gl-sast-container-report.json]

The above example will create a sast:container job in your CI/CD pipeline, pull the image from the Container Registry (whose name is defined from the two CI_APPLICATION_ variables) and scan it for possible vulnerabilities. The report will be saved as an artifact that you can later download and analyze.

If you want to whitelist some specific vulnerabilities, you can do so by defining them in a YAML file, in our case its named clair-whitelist.yml.

Tip: Starting with GitLab Ultimate 10.4, this information will be automatically extracted and shown right in the merge request widget. To do so, the CI/CD job must be named sast:container and the artifact path must be gl-sast-container-report.json. Learn more on application security testing results shown in merge requests.