Chapter 3. Clair security scanner


3.1. Clair vulnerability databases

Clair uses the following vulnerability databases to report for issues in your images:

  • Ubuntu Oval database
  • Debian Security Tracker
  • Red Hat Enterprise Linux (RHEL) Oval database
  • SUSE Oval database
  • Oracle Oval database
  • Alpine SecDB database
  • VMware Photon OS database
  • Amazon Web Services (AWS) UpdateInfo
  • Open Source Vulnerability (OSV) Database

For information about how Clair does security mapping with the different databases, see Claircore Severity Mapping.

3.1.1. Information about Open Source Vulnerability (OSV) database for Clair

Open Source Vulnerability (OSV) is a vulnerability database and monitoring service that focuses on tracking and managing security vulnerabilities in open source software.

OSV provides a comprehensive and up-to-date database of known security vulnerabilities in open source projects. It covers a wide range of open source software, including libraries, frameworks, and other components that are used in software development. For a full list of included ecosystems, see defined ecosystems.

Clair also reports vulnerability and security information for golang, java, and ruby ecosystems through the Open Source Vulnerability (OSV) database.

By leveraging OSV, developers and organizations can proactively monitor and address security vulnerabilities in open source components that they use, which helps to reduce the risk of security breaches and data compromises in projects.

For more information about OSV, see the OSV website.

3.2. Clair on OpenShift Container Platform

To set up Clair v4 (Clair) on a Red Hat Quay deployment on OpenShift Container Platform, it is recommended to use the Red Hat Quay Operator. By default, the Red Hat Quay Operator installs or upgrades a Clair deployment along with your Red Hat Quay deployment and configure Clair automatically.

3.3. Testing Clair

Use the following procedure to test Clair on either a standalone Red Hat Quay deployment, or on an OpenShift Container Platform Operator-based deployment.

Prerequisites

  • You have deployed the Clair container image.

Procedure

  1. Pull a sample image by entering the following command:

    $ podman pull ubuntu:20.04
  2. Tag the image to your registry by entering the following command:

    $ sudo podman tag docker.io/library/ubuntu:20.04 <quay-server.example.com>/<user-name>/ubuntu:20.04
  3. Push the image to your Red Hat Quay registry by entering the following command:

    $ sudo podman push --tls-verify=false quay-server.example.com/quayadmin/ubuntu:20.04
  4. Log in to your Red Hat Quay deployment through the UI.
  5. Click the repository name, for example, quayadmin/ubuntu.
  6. In the navigation pane, click Tags.

    Report summary

    Security scan information appears for scanned repository images

  7. Click the image report, for example, 45 medium, to show a more detailed report:

    Report details

    See all vulnerabilities or only those that are fixable

    Note

    In some cases, Clair shows duplicate reports on images, for example, ubi8/nodejs-12 or ubi8/nodejs-16. This occurs because vulnerabilities with same name are for different packages. This behavior is expected with Clair vulnerability reporting and will not be addressed as a bug.

3.4. Advanced Clair configuration

Use the procedures in the following sections to configure advanced Clair settings.

3.4.1. Unmanaged Clair configuration

Red Hat Quay users can run an unmanaged Clair configuration with the Red Hat Quay OpenShift Container Platform Operator. This feature allows users to create an unmanaged Clair database, or run their custom Clair configuration without an unmanaged database.

An unmanaged Clair database allows the Red Hat Quay Operator to work in a geo-replicated environment, where multiple instances of the Operator must communicate with the same database. An unmanaged Clair database can also be used when a user requires a highly-available (HA) Clair database that exists outside of a cluster.

3.4.1.1. Running a custom Clair configuration with an unmanaged Clair database

Use the following procedure to set your Clair database to unmanaged.

Important

You must not use the same externally managed PostgreSQL database for both Red Hat Quay and Clair deployments. Your PostgreSQL database must also not be shared with other workloads, as it might exhaust the natural connection limit on the PostgreSQL side when connection-intensive workloads, like Red Hat Quay or Clair, contend for resources. Additionally, pgBouncer is not supported with Red Hat Quay or Clair, so it is not an option to resolve this issue.

Procedure

  • In the Quay Operator, set the clairpostgres component of the QuayRegistry custom resource to managed: false:

    apiVersion: quay.redhat.com/v1
    kind: QuayRegistry
    metadata:
      name: quay370
    spec:
      configBundleSecret: config-bundle-secret
      components:
        - kind: objectstorage
          managed: false
        - kind: route
          managed: true
        - kind: tls
          managed: false
        - kind: clairpostgres
          managed: false

3.4.1.2. Configuring a custom Clair database with an unmanaged Clair database

Red Hat Quay on OpenShift Container Platform allows users to provide their own Clair database.

Use the following procedure to create a custom Clair database.

Note

The following procedure sets up Clair with SSL/TLS certifications. To view a similar procedure that does not set up Clair with SSL/TLS certifications, see "Configuring a custom Clair database with a managed Clair configuration".

Procedure

  1. Create a Quay configuration bundle secret that includes the clair-config.yaml by entering the following command:

    $ oc create secret generic --from-file config.yaml=./config.yaml --from-file extra_ca_cert_rds-ca-2019-root.pem=./rds-ca-2019-root.pem --from-file clair-config.yaml=./clair-config.yaml --from-file ssl.cert=./ssl.cert --from-file ssl.key=./ssl.key config-bundle-secret

    Example Clair config.yaml file

    indexer:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslrootcert=/run/certs/rds-ca-2019-root.pem sslmode=verify-ca
        layer_scan_concurrency: 6
        migrations: true
        scanlock_retry: 11
    log_level: debug
    matcher:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslrootcert=/run/certs/rds-ca-2019-root.pem sslmode=verify-ca
        migrations: true
    metrics:
        name: prometheus
    notifier:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslrootcert=/run/certs/rds-ca-2019-root.pem sslmode=verify-ca
        migrations: true

    Note
    • The database certificate is mounted under /run/certs/rds-ca-2019-root.pem on the Clair application pod in the clair-config.yaml. It must be specified when configuring your clair-config.yaml.
    • An example clair-config.yaml can be found at Clair on OpenShift config.
  2. Add the clair-config.yaml file to your bundle secret, for example:

    apiVersion: v1
    kind: Secret
    metadata:
      name: config-bundle-secret
      namespace: quay-enterprise
    data:
      config.yaml: <base64 encoded Quay config>
      clair-config.yaml: <base64 encoded Clair config>
      extra_ca_cert_<name>: <base64 encoded ca cert>
      ssl.crt: <base64 encoded SSL certificate>
      ssl.key: <base64 encoded SSL private key>
    Note

    When updated, the provided clair-config.yaml file is mounted into the Clair pod. Any fields not provided are automatically populated with defaults using the Clair configuration module.

  3. You can check the status of your Clair pod by clicking the commit in the Build History page, or by running oc get pods -n <namespace>. For example:

    $ oc get pods -n <namespace>

    Example output

    NAME                                               READY   STATUS    RESTARTS   AGE
    f192fe4a-c802-4275-bcce-d2031e635126-9l2b5-25lg2   1/1     Running   0          7s

3.4.2. Running a custom Clair configuration with a managed Clair database

In some cases, users might want to run a custom Clair configuration with a managed Clair database. This is useful in the following scenarios:

  • When a user wants to disable specific updater resources.
  • When a user is running Red Hat Quay in an disconnected environment. For more information about running Clair in a disconnected environment, see Clair in disconnected environments.

    Note
    • If you are running Red Hat Quay in an disconnected environment, the airgap parameter of your clair-config.yaml must be set to true.
    • If you are running Red Hat Quay in an disconnected environment, you should disable all updater components.

3.4.2.1. Setting a Clair database to managed

Use the following procedure to set your Clair database to managed.

Procedure

  • In the Quay Operator, set the clairpostgres component of the QuayRegistry custom resource to managed: true:

    apiVersion: quay.redhat.com/v1
    kind: QuayRegistry
    metadata:
      name: quay370
    spec:
      configBundleSecret: config-bundle-secret
      components:
        - kind: objectstorage
          managed: false
        - kind: route
          managed: true
        - kind: tls
          managed: false
        - kind: clairpostgres
          managed: true

3.4.2.2. Configuring a custom Clair database with a managed Clair configuration

Red Hat Quay on OpenShift Container Platform allows users to provide their own Clair database.

Use the following procedure to create a custom Clair database.

Procedure

  1. Create a Quay configuration bundle secret that includes the clair-config.yaml by entering the following command:

    $ oc create secret generic --from-file config.yaml=./config.yaml --from-file extra_ca_cert_rds-ca-2019-root.pem=./rds-ca-2019-root.pem --from-file clair-config.yaml=./clair-config.yaml config-bundle-secret

    Example Clair config.yaml file

    indexer:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslmode=disable
        layer_scan_concurrency: 6
        migrations: true
        scanlock_retry: 11
    log_level: debug
    matcher:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslmode=disable
        migrations: true
    metrics:
        name: prometheus
    notifier:
        connstring: host=quay-server.example.com port=5432 dbname=quay user=quayrdsdb password=quayrdsdb sslmode=disable
        migrations: true

    Note
    • The database certificate is mounted under /run/certs/rds-ca-2019-root.pem on the Clair application pod in the clair-config.yaml. It must be specified when configuring your clair-config.yaml.
    • An example clair-config.yaml can be found at Clair on OpenShift config.
  2. Add the clair-config.yaml file to your bundle secret, for example:

    apiVersion: v1
    kind: Secret
    metadata:
      name: config-bundle-secret
      namespace: quay-enterprise
    data:
      config.yaml: <base64 encoded Quay config>
      clair-config.yaml: <base64 encoded Clair config>
    Note
    • When updated, the provided clair-config.yaml file is mounted into the Clair pod. Any fields not provided are automatically populated with defaults using the Clair configuration module.
  3. You can check the status of your Clair pod by clicking the commit in the Build History page, or by running oc get pods -n <namespace>. For example:

    $ oc get pods -n <namespace>

    Example output

    NAME                                               READY   STATUS    RESTARTS   AGE
    f192fe4a-c802-4275-bcce-d2031e635126-9l2b5-25lg2   1/1     Running   0          7s

3.4.3. Clair in disconnected environments

Note

Currently, deploying Clair in disconnected environments is not supported on IBM Power and IBM Z.

Clair uses a set of components called updaters to handle the fetching and parsing of data from various vulnerability databases. Updaters are set up by default to pull vulnerability data directly from the internet and work for immediate use. However, some users might require Red Hat Quay to run in a disconnected environment, or an environment without direct access to the internet. Clair supports disconnected environments by working with different types of update workflows that take network isolation into consideration. This works by using the clairctl command line interface tool, which obtains updater data from the internet by using an open host, securely transferring the data to an isolated host, and then important the updater data on the isolated host into Clair.

Use this guide to deploy Clair in a disconnected environment.

Note

Currently, Clair enrichment data is CVSS data. Enrichment data is currently unsupported in disconnected environments.

For more information about Clair updaters, see "Clair updaters".

3.4.3.1. Setting up Clair in a disconnected OpenShift Container Platform cluster

Use the following procedures to set up an OpenShift Container Platform provisioned Clair pod in a disconnected OpenShift Container Platform cluster.

3.4.3.1.1. Installing the clairctl command line utility tool for OpenShift Container Platform deployments

Use the following procedure to install the clairctl CLI tool for OpenShift Container Platform deployments.

Procedure

  1. Install the clairctl program for a Clair deployment in an OpenShift Container Platform cluster by entering the following command:

    $ oc -n quay-enterprise exec example-registry-clair-app-64dd48f866-6ptgw -- cat /usr/bin/clairctl > clairctl
    Note

    Unofficially, the clairctl tool can be downloaded

  2. Set the permissions of the clairctl file so that it can be executed and run by the user, for example:

    $ chmod u+x ./clairctl
3.4.3.1.2. Retrieving and decoding the Clair configuration secret for Clair deployments on OpenShift Container Platform

Use the following procedure to retrieve and decode the configuration secret for an OpenShift Container Platform provisioned Clair instance on OpenShift Container Platform.

Prerequisites

  • You have installed the clairctl command line utility tool.

Procedure

  1. Enter the following command to retrieve and decode the configuration secret, and then save it to a Clair configuration YAML:

    $ oc get secret -n quay-enterprise example-registry-clair-config-secret  -o "jsonpath={$.data['config\.yaml']}" | base64 -d > clair-config.yaml
  2. Update the clair-config.yaml file so that the disable_updaters and airgap parameters are set to true, for example:

    ---
    indexer:
      airgap: true
    ---
    matcher:
      disable_updaters: true
    ---
3.4.3.1.3. Exporting the updaters bundle from a connected Clair instance

Use the following procedure to export the updaters bundle from a Clair instance that has access to the internet.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have retrieved and decoded the Clair configuration secret, and saved it to a Clair config.yaml file.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.

Procedure

  • From a Clair instance that has access to the internet, use the clairctl CLI tool with your configuration file to export the updaters bundle. For example:

    $ ./clairctl --config ./config.yaml export-updaters updates.gz
3.4.3.1.4. Configuring access to the Clair database in the disconnected OpenShift Container Platform cluster

Use the following procedure to configure access to the Clair database in your disconnected OpenShift Container Platform cluster.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have retrieved and decoded the Clair configuration secret, and saved it to a Clair config.yaml file.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.
  • You have exported the updaters bundle from a Clair instance that has access to the internet.

Procedure

  1. Determine your Clair database service by using the oc CLI tool, for example:

    $ oc get svc -n quay-enterprise

    Example output

    NAME                                  TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)                             AGE
    example-registry-clair-app            ClusterIP      172.30.224.93    <none>        80/TCP,8089/TCP                     4d21h
    example-registry-clair-postgres       ClusterIP      172.30.246.88    <none>        5432/TCP                            4d21h
    ...

  2. Forward the Clair database port so that it is accessible from the local machine. For example:

    $ oc port-forward -n quay-enterprise service/example-registry-clair-postgres 5432:5432
  3. Update your Clair config.yaml file, for example:

    indexer:
        connstring: host=localhost port=5432 dbname=postgres user=postgres password=postgres sslmode=disable 1
        scanlock_retry: 10
        layer_scan_concurrency: 5
        migrations: true
        scanner:
          repo:
            rhel-repository-scanner: 2
              repo2cpe_mapping_file: /data/cpe-map.json
          package:
            rhel_containerscanner: 3
              name2repos_mapping_file: /data/repo-map.json
    1
    Replace the value of the host in the multiple connstring fields with localhost.
    2
    For more information about the rhel-repository-scanner parameter, see "Mapping repositories to Common Product Enumeration information".
    3
    For more information about the rhel_containerscanner parameter, see "Mapping repositories to Common Product Enumeration information".
3.4.3.1.5. Importing the updaters bundle into the disconnected OpenShift Container Platform cluster

Use the following procedure to import the updaters bundle into your disconnected OpenShift Container Platform cluster.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have retrieved and decoded the Clair configuration secret, and saved it to a Clair config.yaml file.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.
  • You have exported the updaters bundle from a Clair instance that has access to the internet.
  • You have transferred the updaters bundle into your disconnected environment.

Procedure

  • Use the clairctl CLI tool to import the updaters bundle into the Clair database that is deployed by OpenShift Container Platform. For example:

    $ ./clairctl --config ./clair-config.yaml import-updaters updates.gz

3.4.3.2. Setting up a self-managed deployment of Clair for a disconnected OpenShift Container Platform cluster

Use the following procedures to set up a self-managed deployment of Clair for a disconnected OpenShift Container Platform cluster.

3.4.3.2.1. Installing the clairctl command line utility tool for a self-managed Clair deployment on OpenShift Container Platform

Use the following procedure to install the clairctl CLI tool for self-managed Clair deployments on OpenShift Container Platform.

Procedure

  1. Install the clairctl program for a self-managed Clair deployment by using the podman cp command, for example:

    $ sudo podman cp clairv4:/usr/bin/clairctl ./clairctl
  2. Set the permissions of the clairctl file so that it can be executed and run by the user, for example:

    $ chmod u+x ./clairctl
3.4.3.2.2. Deploying a self-managed Clair container for disconnected OpenShift Container Platform clusters

Use the following procedure to deploy a self-managed Clair container for disconnected OpenShift Container Platform clusters.

Prerequisites

  • You have installed the clairctl command line utility tool.

Procedure

  1. Create a folder for your Clair configuration file, for example:

    $ mkdir /etc/clairv4/config/
  2. Create a Clair configuration file with the disable_updaters parameter set to true, for example:

    ---
    indexer:
      airgap: true
    ---
    matcher:
      disable_updaters: true
    ---
  3. Start Clair by using the container image, mounting in the configuration from the file you created:

    $ sudo podman run -it --rm --name clairv4 \
    -p 8081:8081 -p 8088:8088 \
    -e CLAIR_CONF=/clair/config.yaml \
    -e CLAIR_MODE=combo \
    -v /etc/clairv4/config:/clair:Z \
    registry.redhat.io/quay/clair-rhel8:v3.13.1
3.4.3.2.3. Exporting the updaters bundle from a connected Clair instance

Use the following procedure to export the updaters bundle from a Clair instance that has access to the internet.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have deployed Clair.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.

Procedure

  • From a Clair instance that has access to the internet, use the clairctl CLI tool with your configuration file to export the updaters bundle. For example:

    $ ./clairctl --config ./config.yaml export-updaters updates.gz
3.4.3.2.4. Configuring access to the Clair database in the disconnected OpenShift Container Platform cluster

Use the following procedure to configure access to the Clair database in your disconnected OpenShift Container Platform cluster.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have deployed Clair.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.
  • You have exported the updaters bundle from a Clair instance that has access to the internet.

Procedure

  1. Determine your Clair database service by using the oc CLI tool, for example:

    $ oc get svc -n quay-enterprise

    Example output

    NAME                                  TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)                             AGE
    example-registry-clair-app            ClusterIP      172.30.224.93    <none>        80/TCP,8089/TCP                     4d21h
    example-registry-clair-postgres       ClusterIP      172.30.246.88    <none>        5432/TCP                            4d21h
    ...

  2. Forward the Clair database port so that it is accessible from the local machine. For example:

    $ oc port-forward -n quay-enterprise service/example-registry-clair-postgres 5432:5432
  3. Update your Clair config.yaml file, for example:

    indexer:
        connstring: host=localhost port=5432 dbname=postgres user=postgres password=postgres sslmode=disable 1
        scanlock_retry: 10
        layer_scan_concurrency: 5
        migrations: true
        scanner:
          repo:
            rhel-repository-scanner: 2
              repo2cpe_mapping_file: /data/cpe-map.json
          package:
            rhel_containerscanner: 3
              name2repos_mapping_file: /data/repo-map.json
    1
    Replace the value of the host in the multiple connstring fields with localhost.
    2
    For more information about the rhel-repository-scanner parameter, see "Mapping repositories to Common Product Enumeration information".
    3
    For more information about the rhel_containerscanner parameter, see "Mapping repositories to Common Product Enumeration information".
3.4.3.2.5. Importing the updaters bundle into the disconnected OpenShift Container Platform cluster

Use the following procedure to import the updaters bundle into your disconnected OpenShift Container Platform cluster.

Prerequisites

  • You have installed the clairctl command line utility tool.
  • You have deployed Clair.
  • The disable_updaters and airgap parameters are set to true in your Clair config.yaml file.
  • You have exported the updaters bundle from a Clair instance that has access to the internet.
  • You have transferred the updaters bundle into your disconnected environment.

Procedure

  • Use the clairctl CLI tool to import the updaters bundle into the Clair database that is deployed by OpenShift Container Platform:

    $ ./clairctl --config ./clair-config.yaml import-updaters updates.gz

3.4.4. Mapping repositories to Common Product Enumeration information

Note

Currently, mapping repositories to Common Product Enumeration information is not supported on IBM Power and IBM Z.

Clair’s Red Hat Enterprise Linux (RHEL) scanner relies on a Common Product Enumeration (CPE) file to map RPM packages to the corresponding security data to produce matching results. These files are owned by product security and updated daily.

The CPE file must be present, or access to the file must be allowed, for the scanner to properly process RPM packages. If the file is not present, RPM packages installed in the container image will not be scanned.

Table 3.1. Clair CPE mapping files
CPELink to JSON mapping file

repos2cpe

Red Hat Repository-to-CPE JSON

names2repos

Red Hat Name-to-Repos JSON.

In addition to uploading CVE information to the database for disconnected Clair installations, you must also make the mapping file available locally:

  • For standalone Red Hat Quay and Clair deployments, the mapping file must be loaded into the Clair pod.
  • For Red Hat Quay on OpenShift Container Platform deployments, you must set the Clair component to unmanaged. Then, Clair must be deployed manually, setting the configuration to load a local copy of the mapping file.

3.4.4.1. Mapping repositories to Common Product Enumeration example configuration

Use the repo2cpe_mapping_file and name2repos_mapping_file fields in your Clair configuration to include the CPE JSON mapping files. For example:

indexer:
 scanner:
    repo:
      rhel-repository-scanner:
        repo2cpe_mapping_file: /data/cpe-map.json
    package:
      rhel_containerscanner:
        name2repos_mapping_file: /data/repo-map.json

For more information, see How to accurately match OVAL security data to installed RPMs.

Red Hat logoGithubRedditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

© 2024 Red Hat, Inc.