Static Application Security Testing (SAST)

DETAILS: Tier: Free, Premium, Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

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If you're using GitLab CI/CD, you can use Static Application Security Testing (SAST) to check your source code for known vulnerabilities. You can run SAST analyzers in any GitLab tier. The analyzers output JSON-formatted reports as job artifacts.

With GitLab Ultimate, SAST results are also processed so you can:

• Use them in approval workflows.
• Review them in the security dashboard.

For more details, see the Summary of features per tier.

A pipeline consists of multiple jobs, including SAST and DAST scanning. If any job fails to finish for any reason, the security dashboard does not show SAST scanner output. For example, if the SAST job finishes but the DAST job fails, the security dashboard does not show SAST results. On failure, the analyzer outputs an exit code.

Requirements

SAST 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.

To run SAST jobs, by default, you need GitLab Runner with the docker or kubernetes executor. If you're using SaaS runners on GitLab.com, this is enabled by default.

NOTE: GitLab SAST analyzers only run in a Docker on Linux amd64 environment, which is not Docker 19.03.0. See Docker error for details.

Supported languages and frameworks

GitLab SAST supports scanning a variety of programming languages and frameworks. Once you enable SAST, the right set of analyzers runs automatically even if your project uses more than one language.

For more information about our plans for language support in SAST, see the category direction page.

1. The SpotBugs-based analyzer supports Gradle, Maven, and SBT. It can also be used with variants like the Gradle wrapper, Grails, and the Maven wrapper. However, SpotBugs has limitations when used against Ant-based projects. You should use the Semgrep-based analyzer for Ant-based Java or Scala projects.
2. Requires a custom ruleset and an override to the semgrep-sast CI job. See Scanning Rust applications for an example.

End of supported analyzers

The following GitLab analyzers have reached End of Support status and do not receive updates. They were replaced by the Semgrep-based analyzer with GitLab-managed rules.

Multi-project support

GitLab SAST can scan repositories that contain multiple projects.

The following analyzers have multi-project support:

• Kubesec
• PMD
• Semgrep
• SpotBugs
• Sobelow

Enable multi-project support for Security Code Scan

Multi-project support in the Security Code Scan requires a Solution (.sln) file in the root of the repository. For details on the Solution format, see the Microsoft reference Solution (.sln) file.

Advanced vulnerability tracking

DETAILS: Tier: Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

Source code is volatile; as developers make changes, source code may move within files or between files. Security analyzers may have already reported vulnerabilities that are being tracked in the Vulnerability Report. These vulnerabilities are linked to specific problematic code fragments so that they can be found and fixed. If the code fragments are not tracked reliably as they move, vulnerability management is harder because the same vulnerability could be reported again.

GitLab SAST uses an advanced vulnerability tracking algorithm to more accurately identify when the same vulnerability has moved within a file due to refactoring or unrelated changes.

Advanced vulnerability tracking is available in a subset of the supported languages and analyzers:

• C, in the Semgrep-based only
• C++, in the Semgrep-based only
• C#, in the Semgrep-based analyzer only
• Go, in the Semgrep-based analyzer only
• Java, in the Semgrep-based analyzer only
• JavaScript, in the Semgrep-based analyzer only
• PHP, in the Semgrep-based analyzer only
• Python, in the Semgrep-based analyzer only
• Ruby, in the Semgrep-based analyzer only

Support for more languages and analyzers is tracked in this epic.

For more information, see the confidential project https://gitlab.com/gitlab-org/security-products/post-analyzers/tracking-calculator. The content of this project is available only to GitLab team members.

Automatic vulnerability resolution

• Introduced in GitLab 15.9 with a project-level flag named sec_mark_dropped_findings_as_resolved.
• Enabled by default in GitLab 15.10. On GitLab.com, contact Support if you need to disable the flag for your project.
• Feature flag removed in GitLab 16.2.

To help you focus on the vulnerabilities that are still relevant, GitLab SAST automatically resolves vulnerabilities when:

• You disable a predefined rule.
• We remove a rule from the default ruleset.

Automatic resolution is available only for findings from the Semgrep-based analyzer. The Vulnerability Management system leaves a comment on automatically-resolved vulnerabilities so you still have a historical record of the vulnerability.

If you re-enable the rule later, the findings are reopened for triage.

Supported distributions

The default scanner images are built on a base Alpine image for size and maintainability.

FIPS-enabled images

GitLab offers an image version, based on the Red Hat UBI base image, that uses a FIPS 140-validated cryptographic module. To use the FIPS-enabled image, you can either:

• Set the SAST_IMAGE_SUFFIX to -fips.
• Add the -fips extension to the default image name.

For example:

variables:
  SAST_IMAGE_SUFFIX: '-fips'

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

A FIPS-compliant image is only available for the Semgrep-based analyzer.

WARNING: To use SAST in a FIPS-compliant manner, you must exclude other analyzers from running. If you use a FIPS-enabled image to run Semgrep in a runner with non-root user, you must update the run_as_user attribute under runners.kubernetes.pod_security_context to use the ID of gitlab user created by the image, which is 1000.

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 | |:---------------------------------------------------------------- -|:--------------------|:-------------------| | Automatically scan code with appropriate analyzers | {check-circle} | {check-circle} | | Configure SAST scanners | {check-circle} | {check-circle} | | Customize SAST settings | {check-circle} | {check-circle} | | Download SAST output | {check-circle} | {check-circle} | | See new findings in merge request widget | {dotted-circle} | {check-circle} | | See new findings in merge request changes | {dotted-circle} | {check-circle} | | Manage vulnerabilities | {dotted-circle} | {check-circle} | | Access the Security Dashboard | {dotted-circle} | {check-circle} | | Configure SAST by using the UI | {dotted-circle} | {check-circle} | | Customize SAST rulesets | {dotted-circle} | {check-circle} | | Track moved vulnerabilities | {dotted-circle} | {check-circle} |

Output

SAST outputs the file gl-sast-report.json as a job artifact. The file contains details of all detected vulnerabilities. You can download the file for processing outside GitLab.

For more information, see:

• SAST report file schema
• Example SAST report file

View SAST results

The SAST report file is processed by GitLab and the details are shown in the UI:

• Merge request widget
• Merge request changes view
• Vulnerability report

Merge request widget

DETAILS: Tier: Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

SAST results display in the merge request widget area if a report from the target branch is available for comparison. The merge request widget displays SAST results and resolutions that were introduced by the changes made in the merge request.

Merge request changes view

DETAILS: Tier: Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

• Introduced in GitLab 16.6 with a flag named sast_reports_in_inline_diff. Disabled by default.
• Enabled by default in GitLab 16.8.
• Feature flag removed in GitLab 16.9.

SAST results display in the merge request Changes view. Lines containing SAST issues are marked by a symbol beside the gutter. Select the symbol to see the list of issues, then select an issue to see its details.

Contribute your scanner

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

Configuration

SAST scanning runs in your CI/CD pipeline. When you add the GitLab-managed CI/CD template to your pipeline, the right SAST analyzers automatically scan your code and save results as SAST report artifacts.

To configure SAST for a project you can:

• Use Auto SAST, provided by Auto DevOps.
• Configure SAST in your CI/CD YAML.
• Configure SAST by using the UI.

You can enable SAST across many projects by enforcing scan execution.

Configure SAST in your CI/CD YAML

To enable SAST, you include the SAST.gitlab-ci.yml template. The template is provided as a part of your GitLab installation.

Copy and paste the following to the bottom of the .gitlab-ci.yml file. If an include line already exists, add only the template line below it.

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

The included template creates SAST jobs in your CI/CD pipeline and scans your project's source code for possible vulnerabilities.

The results are saved as a SAST report artifact that you can later download and analyze. When downloading, you always receive the most recent SAST artifact available.

Configure SAST by using the UI

You can enable and configure SAST by using the UI, either with the default settings or with customizations. The method you can use depends on your GitLab license tier.

Configure SAST with customizations

DETAILS: Tier: Ultimate Offering: GitLab.com, Self-managed, GitLab Dedicated

Removed individual SAST analyzers configuration options from the UI in GitLab 16.2.

NOTE: The configuration tool works best with no existing .gitlab-ci.yml file, or with a minimal configuration file. If you have a complex GitLab configuration file it may not be parsed successfully, and an error may occur.

To enable and configure SAST with customizations:

1. On the left sidebar, select Search or go to and find your project.

2. Select Secure > Security configuration.

3. If the project does not have a .gitlab-ci.yml file, select Enable SAST in the Static Application Security Testing (SAST) row, otherwise select Configure SAST.

4. Enter the custom SAST values.

   Custom values are stored in the .gitlab-ci.yml file. For CI/CD variables not in the SAST Configuration page, their values are inherited from the GitLab SAST template.

5. Select Create Merge Request.

6. Review and merge the merge request.

Pipelines now include a SAST job.

Configure SAST with default settings only

NOTE: The configuration tool works best with no existing .gitlab-ci.yml file, or with a minimal configuration file. If you have a complex GitLab configuration file it may not be parsed successfully, and an error may occur.

To enable and configure SAST with default settings:

1. On the left sidebar, select Search or go to and find your project.
2. Select Secure > Security configuration.
3. In the SAST section, select Configure with a merge request.
4. Review and merge the merge request to enable SAST.

Pipelines now include a SAST job.

Overriding SAST jobs

To override a job definition, (for example, change properties like variables, dependencies, or rules), declare a job with the same name as the SAST job to override. Place this new job after the template inclusion and specify any additional keys under it. For example, this enables FAIL_NEVER for the spotbugs analyzer:

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

spotbugs-sast:
  variables:
    FAIL_NEVER: 1

Pinning to minor image 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.gitlab-ci.yml template.

Only set this variable within 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 semgrep analyzer and a specific patch version of the brakeman analyzer:

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

semgrep-sast:
  variables:
    SAST_ANALYZER_IMAGE_TAG: "3.7"

brakeman-sast:
  variables:
    SAST_ANALYZER_IMAGE_TAG: "3.1.1"

Using CI/CD variables to pass credentials for private repositories

Some analyzers require downloading the project's dependencies to perform the analysis. In turn, such dependencies may live in private Git repositories and thus require credentials like username and password to download them. Depending on the analyzer, such credentials can be provided to it via custom CI/CD variables.

Using a CI/CD variable to pass username and password to a private Go repository

If your Go project depends on private modules, see Fetch modules from private projects for how to provide authentication over HTTPS.

To specify credentials via ~/.netrc provide a before_script containing the following:

gosec-sast:
  before_script:
    - |
      cat <<EOF > ~/.netrc
      machine gitlab.com
      login $CI_DEPLOY_USER
      password $CI_DEPLOY_PASSWORD
      EOF

Using a CI/CD variable to pass username and password to a private Maven repository

If your private Maven repository requires login credentials, you can use the MAVEN_CLI_OPTS CI/CD variable.

Read more on how to use private Maven repositories.

Enabling Kubesec analyzer

You need to set SCAN_KUBERNETES_MANIFESTS to "true" to enable the Kubesec analyzer. In .gitlab-ci.yml, define:

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

variables:
  SCAN_KUBERNETES_MANIFESTS: "true"

Scanning Rust applications

To scan Rust applications, you must:

1. Provide a custom ruleset for Rust. Create a file named sast-ruleset.toml in a .gitlab/ directory at the root of your repository. Add the following contents:

   [semgrep]
     description = "Rust ruleset for Semgrep"
     targetdir = "/sgrules"
     timeout = 60
   
     [[semgrep.passthrough]]
       type  = "url"
       value = "https://semgrep.dev/c/p/rust"
       target = "rust.yml"

   This configuration uses the open-source Semgrep ruleset. Read more on customizing rulesets.

2. Override the semgrep-sast job to add a rule that detects Rust (.rs) files. Define the following in the .gitlab-ci.yml file:

   include:
     - template: Jobs/SAST.gitlab-ci.yml
    
   semgrep-sast:
     rules:
       - if: $CI_COMMIT_BRANCH
         exists:
           - '**/*.rs'
           # include any other file extensions you need to scan from the semgrep-sast template: Jobs/SAST.gitlab-ci.yml 

Pre-compilation

Most GitLab SAST analyzers directly scan your source code without compiling it first. However, for technical reasons, some analyzers can only scan compiled code.

By default, these analyzers automatically attempt to fetch dependencies and compile your code so it can be scanned. Automatic compilation can fail if:

• your project requires custom build configurations.
• you use language versions that aren't built into the analyzer.

To resolve these issues, you can skip the analyzer's compilation step and directly provide artifacts from an earlier stage in your pipeline instead. This strategy is called pre-compilation.

Pre-compilation is available for the analyzers that support the COMPILE CI/CD variable. See Analyzer settings for the current list.

To use pre-compilation:

1. Output your project's dependencies to a directory in the project's working directory, then save that directory as an artifact by setting the artifacts: paths configuration.
2. Provide the COMPILE: "false" CI/CD variable to the analyzer to disable automatic compilation.
3. Add your compilation stage as a dependency for the analyzer job.

To allow the analyzer to recognize the compiled artifacts, you must explicitly specify the path to the vendored directory. This configuration can vary per analyzer. For Maven projects, you can use MAVEN_REPO_PATH. See Analyzer settings for the complete list of available options.

The following example pre-compiles a Maven project and provides it to the SpotBugs SAST analyzer:

stages:
  - build
  - test

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

build:
  image: maven:3.6-jdk-8-slim
  stage: build
  script:
    - mvn package -Dmaven.repo.local=./.m2/repository
  artifacts:
    paths:
      - .m2/
      - target/

spotbugs-sast:
  dependencies:
    - build
  variables:
    MAVEN_REPO_PATH: $CI_PROJECT_DIR/.m2/repository
    COMPILE: "false"
  artifacts:
    reports:
      sast: gl-sast-report.json

Running jobs in merge request pipelines

See Use security scanning tools with merge request pipelines.

Available CI/CD variables

SAST can be configured using the variables parameter in .gitlab-ci.yml.

WARNING: All customization of GitLab security scanning tools should be tested in a merge request before merging these changes to the default branch. Failure to do so can give unexpected results, including a large number of false positives.

The following example includes the SAST template to override the SEARCH_MAX_DEPTH variable to 10. The template is evaluated before the pipeline configuration, so the last mention of the variable takes precedence.

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

variables:
  SEARCH_MAX_DEPTH: 10

Custom Certificate Authority

To trust a custom Certificate Authority, set the ADDITIONAL_CA_CERT_BUNDLE variable to the bundle of CA certs that you want to trust in the SAST environment. The ADDITIONAL_CA_CERT_BUNDLE value should contain the text representation of the X.509 PEM public-key certificate. For example, to configure this value in the .gitlab-ci.yml file, use the following:

variables:
  ADDITIONAL_CA_CERT_BUNDLE: |
      -----BEGIN CERTIFICATE-----
      MIIGqTCCBJGgAwIBAgIQI7AVxxVwg2kch4d56XNdDjANBgkqhkiG9w0BAQsFADCB
      ...
      jWgmPqF3vUbZE0EyScetPJquRFRKIesyJuBFMAs=
      -----END CERTIFICATE-----

The ADDITIONAL_CA_CERT_BUNDLE value can also be configured as a custom variable in the UI, either as a file, which requires the path to the certificate, or as a variable, which requires the text representation of the certificate.

Docker images

The following are Docker image-related CI/CD variables.

Vulnerability filters

Some analyzers make it possible to filter out vulnerabilities under a given threshold.

Analyzer settings

Some analyzers can be customized with CI/CD variables.

| PHPCS_SECURITY_AUDIT_PHP_EXTENSIONS | phpcs-security-audit | Comma separated list of additional PHP Extensions. | | SAST_SEMGREP_METRICS | Semgrep | Set to "false" to disable sending anonymized scan metrics to r2c. Default: true. | | SAST_SCANNER_ALLOWED_CLI_OPTS | Semgrep | CLI options (arguments with value, or flags) that are passed to the underlying security scanner when running scan operation. Only a limited set of options are accepted. Separate a CLI option and its value using either a blank space or equals (=) character. For example: name1 value1 or name1=value1. Multiple options must be separated by blank spaces. For example: name1 value1 name2 value2. Introduced in GitLab 15.3. | | SAST_RULESET_GIT_REFERENCE | Semgrep and nodejs-scan | Defines a path to a custom ruleset configuration. If a project has a .gitlab/sast-ruleset.toml file committed, that local configuration takes precedence and the file from SAST_RULESET_GIT_REFERENCE isn’t used. This variable is available for the Ultimate tier only. |

Security scanner configuration

SAST analyzers internally use OSS security scanners to perform the analysis. We set the recommended configuration for the security scanner so that you need not to worry about tuning them. However, there can be some rare cases where our default scanner configuration does not suit your requirements.

To allow some customization of scanner behavior, you can add a limited set of flags to the underlying scanner. Specify the flags in the SAST_SCANNER_ALLOWED_CLI_OPTS CI/CD variable. These flags are added to the scanner's CLI options.

Custom CI/CD variables

In addition to the aforementioned SAST configuration CI/CD variables, all custom variables are propagated to the underlying SAST analyzer images if the SAST vendored template is used.

Running SAST in an offline environment

For self-managed GitLab instances in an environment with limited, restricted, or intermittent access to external resources through the internet, some adjustments are required for the SAST job to run successfully. For more information, see Offline environments.

Requirements for offline SAST

To use SAST in an offline environment, you need:

• GitLab Runner with the docker or kubernetes executor.
• A Docker container registry with locally available copies of SAST analyzer images.
• Configure certificate checking of packages (optional).

GitLab Runner has a default pull_policy of always, meaning the runner tries to pull Docker images from the GitLab container registry even if a local copy is available. The GitLab Runner pull_policy can be set to if-not-present in an offline environment if you prefer using only locally available Docker images. However, we recommend keeping the pull policy setting to always if not in an offline environment, as this enables the use of updated scanners in your CI/CD pipelines.

Make GitLab SAST analyzer images available inside your Docker registry

For SAST with all supported languages and frameworks, import the following default SAST analyzer images from registry.gitlab.com into your local Docker container registry:

registry.gitlab.com/security-products/kubesec:5
registry.gitlab.com/security-products/pmd-apex:5
registry.gitlab.com/security-products/semgrep:5
registry.gitlab.com/security-products/sobelow:5
registry.gitlab.com/security-products/spotbugs:5

The process for importing Docker images into a local offline Docker registry depends on your network security policy. Consult your IT staff to find an accepted and approved process by which external resources can be imported or temporarily accessed. These scanners are periodically updated with new definitions, and you may be able to make occasional updates on your own.

For details on saving and transporting Docker images as a file, see the Docker documentation on docker save, docker load, docker export, and docker import.

If support for Custom Certificate Authorities are needed

Support for custom certificate authorities was introduced in the following versions.

1. These analyzers reached End of Support in GitLab 15.4.

Set SAST CI/CD variables to use local SAST analyzers

Add the following configuration to your .gitlab-ci.yml file. You must replace SECURE_ANALYZERS_PREFIX to refer to your local Docker container registry:

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

variables:
  SECURE_ANALYZERS_PREFIX: "localhost:5000/analyzers"

The SAST job should now use local copies of the SAST analyzers to scan your code and generate security reports without requiring internet access.

Configure certificate checking of packages

If a SAST job invokes a package manager, you must configure its certificate verification. In an offline environment, certificate verification with an external source is not possible. Either use a self-signed certificate or disable certificate verification. Refer to the package manager's documentation for instructions.

Running SAST in SELinux

By default SAST analyzers are supported in GitLab instances hosted on SELinux. Adding a before_script in an overridden SAST job may not work as runners hosted on SELinux have restricted permissions.