Infrastructure as Code (IaC) Scanning

Introduced in GitLab 14.5.

Infrastructure as Code (IaC) Scanning scans your IaC configuration files for known vulnerabilities.

IaC Scanning supports configuration files for Terraform, Ansible, AWS CloudFormation, and Kubernetes.

Requirements

IaC Scanning runs in the test stage, which is available by default. If you redefine the stages in the .gitlab-ci.yml file, the test stage is required.

We recommend a minimum of 4 GB RAM to ensure consistent performance.

To run IaC Scanning jobs, by default, you need GitLab Runner with the docker or kubernetes executor. If you’re using the shared runners on GitLab.com, this is enabled by default.

caution
GitLab IaC Scanning analyzers don’t support running on Windows or on any CPU architectures other than amd64.
caution
If you use your own runners, make sure the Docker version installed is not 19.03.0. See troubleshooting information for details.

Supported languages and frameworks

GitLab IaC Scanning supports a variety of IaC configuration files. Our IaC security scanners also feature automatic language detection which works even for mixed-language projects. If any supported configuration files are detected in project source code we automatically run the appropriate IaC analyzers.

Configuration file type Scan tool Introduced in GitLab version
Ansible KICS 14.5
AWS CloudFormation KICS 14.5
Azure Resource Manager 1 KICS 14.5
Dockerfile KICS 14.5
Google Deployment Manager KICS 14.5
Kubernetes KICS 14.5
OpenAPI KICS 14.5
Terraform 2 KICS 14.5
  1. IaC Scanning can analyze Azure Resource Manager templates in JSON format. If you write templates in the Bicep language, you must use the bicep CLI to convert your Bicep files into JSON before GitLab IaC Scanning can analyze them.
  2. Terraform modules in a custom registry are not scanned for vulnerabilities. You can follow this issue for the proposed feature.

Supported distributions

GitLab scanners are provided with a base alpine image for size and maintainability.

FIPS-enabled images

Introduced in GitLab 14.10.

GitLab also offers FIPS-enabled Red Hat UBI versions of the images. You can therefore replace standard images with FIPS-enabled images. To configure the images, set the SAST_IMAGE_SUFFIX to -fips or modify the standard tag plus the -fips extension. 

variables:
  SAST_IMAGE_SUFFIX: '-fips'

include:
  - template: Jobs/SAST-IaC.gitlab-ci.yml

Making IaC analyzers available to all GitLab tiers

All open source (OSS) analyzers are available with the GitLab Free tier. Future proprietary analyzers may be restricted to higher tiers.

Summary of features per tier

Different features are available in different GitLab tiers, as shown in the following table:

Capability In Free & Premium In Ultimate
Configure IaC scanner
Download JSON Report
See new findings in merge request widget
Manage vulnerabilities
Access the Security Dashboard

Contribute your scanner

The Security Scanner Integration documentation explains how to integrate other security scanners into GitLab.

Configuration

To configure IaC Scanning for a project you can:

Configure IaC Scanning manually

To enable IaC Scanning you must include the SAST-IaC.gitlab-ci.yml template provided as part of your GitLab installation. Here is an example of how to include it: 

include:
  - template: Jobs/SAST-IaC.gitlab-ci.yml

The included template creates IaC Scanning jobs in your CI/CD pipeline and scans your project’s configuration files for possible vulnerabilities.

The results are saved as a SAST report artifact that you can download and analyze.

Enable IaC Scanning via an automatic merge request

To enable IaC Scanning in a project, you can create a merge request:

  1. On the top bar, select Main menu > Projects and find your project.
  2. On the left sidebar, select Security & Compliance > Configuration.
  3. In the Infrastructure as Code (IaC) Scanning row, select Configure with a merge request.
  4. Review and merge the merge request to enable IaC Scanning.

Pipelines now include an IaC Scanning job.

Customize rulesets

Added support for overriding rules in GitLab 14.8.

You can customize the default IaC Scanning rules provided with GitLab.

The following customization options can be used separately, or together:

Disable predefined analyzer rules

If there are specific IaC Scanning rules that you don’t want active, you can disable them.

To disable analyzer rules:

  1. Create a .gitlab directory at the root of your project, if one doesn’t already exist.
  2. Create a custom ruleset file named sast-ruleset.toml in the .gitlab directory, if one doesn’t already exist.
  3. Set the disabled flag to true in the context of a ruleset section.
  4. In one or more ruleset subsections, list the rules to disable. Every ruleset.identifier section has:
    • A type field for the rule. For IaC Scanning, the identifier type is kics_id.
    • A value field for the rule identifier. KICS rule identifiers are alphanumeric strings. To find the rule identifier, you can:

In the following example sast-ruleset.toml file, the disabled rules are assigned to the kics analyzer by matching the type and value of identifiers: 

[kics]
  [[kics.ruleset]]
    disable = true
    [kics.ruleset.identifier]
      type = "kics_id"
      value = "8212e2d7-e683-49bc-bf78-d6799075c5a7"

  [[kics.ruleset]]
    disable = true
    [kics.ruleset.identifier]
      type = "kics_id"
      value = "b03a748a-542d-44f4-bb86-9199ab4fd2d5"

Override predefined analyzer rules

If there are specific IaC Scanning rules you want to customize, you can override them. For example, you might lower the severity of a rule or link to your own documentation about how to fix a finding.

To override rules:

  1. Create a .gitlab directory at the root of your project, if one doesn’t already exist.
  2. Create a custom ruleset file named sast-ruleset.toml in the .gitlab directory, if one doesn’t already exist.
  3. In one or more ruleset.identifier subsections, list the rules to override. Every ruleset.identifier section has:
    • A type field for the rule. For IaC Scanning, the identifier type is kics_id.
    • A value field for the rule identifier. KICS rule identifiers are alphanumeric strings. To find the rule identifier, you can:
  4. In the ruleset.override context of a ruleset section, provide the keys to override. Any combination of keys can be overridden. Valid keys are:
    • description
    • message
    • name
    • severity (valid options are: Critical, High, Medium, Low, Unknown, Info)

In the following example sast-ruleset.toml file, rules are matched by the type and value of identifiers and then overridden: 

[kics]
  [[kics.ruleset]]
    [kics.ruleset.identifier]
      type = "kics_id"
      value = "8212e2d7-e683-49bc-bf78-d6799075c5a7"
    [kics.ruleset.override]
      description = "OVERRIDDEN description"
      message = "OVERRIDDEN message"
      name = "OVERRIDDEN name"
      severity = "Info"

Pinning to specific analyzer version

The GitLab-managed CI/CD template specifies a major version and automatically pulls the latest analyzer release within that major version.

In some cases, you may need to use a specific version. For example, you might need to avoid a regression in a later release.

To override the automatic update behavior, set the SAST_ANALYZER_IMAGE_TAG CI/CD variable in your CI/CD configuration file after you include the SAST-IaC.gitlab-ci.yml template.

Only set this variable in a specific job. If you set it at the top level, the version you set is used for other SAST analyzers.

You can set the tag to:

  • A major version, like 3. Your pipelines use any minor or patch updates that are released within this major version.
  • A minor version, like 3.7. Your pipelines use any patch updates that are released within this minor version.
  • A patch version, like 3.7.0. Your pipelines don’t receive any updates.

This example uses a specific minor version of the KICS analyzer: 

include:
  - template: Security/SAST-IaC.gitlab-ci.yml

kics-iac-sast:
  variables:
    SAST_ANALYZER_IMAGE_TAG: "3.1"

Reports JSON format

The IaC tool emits a JSON report file in the existing SAST report format. For more information, see the schema for this report.

The JSON report file can be downloaded from the CI pipelines page, or the pipelines tab on merge requests by setting artifacts: paths to gl-sast-report.json. For more information see Downloading artifacts.

Troubleshooting

IaC debug logging

To help troubleshoot IaC jobs, you can increase the Secure scanner log verbosity by using a global CI/CD variable set to debug: 

variables:
  SECURE_LOG_LEVEL: "debug"

IaC Scanning findings show as No longer detected unexpectedly

If a previously detected finding unexpectedly shows as No longer detected, it might be due to an update to the scanner. An update can disable rules that are found to be ineffective or false positives, and the findings are marked as No longer detected:

exec /bin/sh: exec format error message in job log

The GitLab IaC Scanning analyzer only supports running on the amd64 CPU architecture. This message indicates that the job is being run on a different architecture, such as arm.