Static Application Security Testing (SAST) (ULTIMATE)

Introduced in GitLab Ultimate 10.3.

NOTE: Note: The whitepaper "A Seismic Shift in Application Security" explains how 4 of the top 6 attacks were application based. Download it to learn how to protect your organization.

Overview

If you're using GitLab CI/CD, you can analyze your source code for known vulnerabilities using Static Application Security Testing (SAST).

You can take advantage of SAST by doing one of the following:

GitLab checks the SAST report, compares the found vulnerabilities between the source and target branches, and shows the information right on the merge request.

SAST Widget

The results are sorted by the priority of the vulnerability:

  1. Critical
  2. High
  3. Medium
  4. Low
  5. Unknown
  6. Everything else

NOTE: Note: A pipeline consists of multiple jobs, including SAST and DAST scanning. If any job fails to finish for any reason, the security dashboard won't show SAST scanner output. For example, if the SAST job finishes but the DAST job fails, the security dashboard won't show SAST results. The analyzer will output an exit code on failure.

Use cases

  • Your code has a potentially dangerous attribute in a class, or unsafe code that can lead to unintended code execution.
  • Your application is vulnerable to cross-site scripting (XSS) attacks that can be leveraged to unauthorized access to session data.

Requirements

To run SAST 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.

Beginning with GitLab 13.0, Docker privileged mode is necessary only if you've enabled Docker-in-Docker for SAST.

CAUTION: Caution: Our SAST jobs currently expect a Linux container type. Windows containers are not yet supported.

CAUTION: 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

The following table shows which languages, package managers and frameworks are supported and which tools are used.

Language (package managers) / framework Scan tool Introduced in GitLab Version
.NET Core Security Code Scan 11.0
.NET Framework Security Code Scan 13.0
Any Gitleaks and TruffleHog 11.9
Apex (Salesforce) PMD 12.1
C/C++ Flawfinder 10.7
Elixir (Phoenix) Sobelow 11.10
Go Gosec 10.7
Groovy (Ant, Gradle, Maven and SBT) SpotBugs with the find-sec-bugs plugin 11.3 (Gradle) & 11.9 (Ant, Maven, SBT)
Helm Charts Kubesec 13.1
Java (Ant, Gradle, Maven and SBT) SpotBugs with the find-sec-bugs plugin 10.6 (Maven), 10.8 (Gradle) & 11.9 (Ant, SBT)
JavaScript ESLint security plugin 11.8, moved to GitLab Core in 13.2
Kubernetes manifests Kubesec 12.6
Node.js NodeJsScan 11.1
PHP phpcs-security-audit 10.8
Python (pip) bandit 10.3
React ESLint react plugin 12.5
Ruby on Rails brakeman 10.3, moved to GitLab Core in 13.1
Scala (Ant, Gradle, Maven and SBT) SpotBugs with the find-sec-bugs plugin 11.0 (SBT) & 11.9 (Ant, Gradle, Maven)
TypeScript ESLint security plugin 11.9, merged with ESLint in 13.2

NOTE: Note: The Java analyzers can also be used for variants like the Gradle wrapper, Grails and the Maven wrapper.

Making SAST analyzers available to all GitLab tiers

All open source (OSS) analyzers are in the process of being reviewed and potentially moved to the GitLab Core tier. Progress can be tracked in the corresponding epic.

Please note that support for Docker-in-Docker will not be extended to the GitLab Core tier.

Summary of features per tier

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

Capability In Core In Ultimate
Configure SAST Scanners {check-circle} {check-circle}
Customize SAST Settings {check-circle} {check-circle}
View JSON Report {check-circle} {check-circle}
Presentation of JSON Report in Merge Request {dotted-circle} {check-circle}
Interaction with Vulnerabilities {dotted-circle} {check-circle}
Access to Security Dashboard {dotted-circle} {check-circle}

Contribute your scanner

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

Configuration

NOTE: Note: You don't have to configure SAST manually as shown in this section if you're using Auto SAST provided by Auto DevOps.

For GitLab 11.9 and later, to enable SAST you must include the SAST.gitlab-ci.yml template provided as a part of your GitLab installation. For GitLab versions earlier than 11.9, you can copy and use the job as defined that template.

Add the following to your .gitlab-ci.yml file:

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

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

The results will be saved as a SAST report artifact that you can later download and analyze. Due to implementation limitations, we always take the latest SAST artifact available.

Customizing the SAST settings

The SAST settings can be changed through environment variables by using the variables parameter in .gitlab-ci.yml. In the following example, we include the SAST template and at the same time we set the SAST_GOSEC_LEVEL variable to 2:

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

variables:
  SAST_GOSEC_LEVEL: 2

Because the template is evaluated before the pipeline configuration, the last mention of the variable takes precedence.

Overriding SAST jobs

CAUTION: Deprecation: Beginning in GitLab 13.0, the use of only and except is no longer supported. When overriding the template, you must use rules instead.

To override a job definition, (for example, change properties like variables or dependencies), 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: SAST.gitlab-ci.yml

spotbugs-sast:
  variables:
    FAIL_NEVER: 1

Using environment variables to pass credentials for private repositories

Some analyzers require downloading the project's dependencies in order 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 environment variables.

Using a 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 environment variable.

Read more on how to use private Maven repositories.

Enabling Docker-in-Docker

If needed, you can enable Docker-in-Docker to restore the SAST behavior that existed prior to GitLab 13.0. Follow these steps to do so:

  1. Configure GitLab Runner with Docker-inDocker in privileged mode.

  2. Set the variable SAST_DISABLE_DIND set to false:

    include:
      - template: SAST.gitlab-ci.yml
    
    variables:
      SAST_DISABLE_DIND: "false"

This creates a single sast job in your CI/CD pipeline instead of multiple <analyzer-name>-sast jobs.

Enabling Kubesec analyzer

Introduced in GitLab Ultimate 12.6.

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

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

variables:
  SCAN_KUBERNETES_MANIFESTS: "true"

Pre-compilation

If your project requires custom build configurations, it can be preferable to avoid compilation during your SAST execution and instead pass all job artifacts from an earlier stage within the pipeline. This is the current strategy when requiring a before_script execution to prepare your scan job.

To pass your project's dependencies as artifacts, the dependencies must be included in the project's working directory and specified using the artifacts:path configuration. If all dependencies are present, the COMPILE=false variable can be provided to the analyzer and compilation will be skipped:

image: maven:3.6-jdk-8-alpine

stages:
 - build
 - test

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

build:
  stage: build
  script:
    - mvn package -Dmaven.repo.local=./.m2/repository
  artifacts:
    paths:
      - .m2/
      - target/

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

NOTE: Note: The path to the vendored directory must be specified explicitly to allow the analyzer to recognize the compiled artifacts. This configuration can vary per analyzer but in the case of Java above, MAVEN_REPO_PATH can be used. See Analyzer settings for the complete list of available options.

Available variables

SAST can be configured using environment variables.

Logging Level

You can control the verbosity of logs by setting the SECURE_LOG_LEVEL env var. The default is set to info, you can set it to any of the following levels:

  • fatal
  • error
  • warn
  • info
  • debug

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 within the SAST environment.

Docker images

The following are Docker image-related variables.

Environment variable Description
SECURE_ANALYZERS_PREFIX Override the name of the Docker registry providing the default images (proxy). Read more about customizing analyzers.
SAST_ANALYZER_IMAGE_TAG DEPRECATED: Override the Docker tag of the default images. Read more about customizing analyzers.
SAST_DEFAULT_ANALYZERS Override the names of default images. Read more about customizing analyzers.
SAST_DISABLE_DIND Disable Docker-in-Docker and run analyzers individually. This variable is true by default.

Vulnerability filters

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

Environment variable Default value Description
SAST_EXCLUDED_PATHS spec, test, tests, tmp Exclude vulnerabilities from output based on the paths. This is a comma-separated list of patterns. Patterns can be globs, or file or folder paths (for example, doc,spec ). Parent directories will also match patterns.
SAST_BANDIT_EXCLUDED_PATHS Comma-separated list of paths to exclude from scan. Uses Python's fnmatch syntax; For example: '*/tests/*, */venv/*'
SAST_BRAKEMAN_LEVEL 1 Ignore Brakeman vulnerabilities under given confidence level. Integer, 1=Low 3=High.
SAST_DISABLE_BABEL false Disable Babel processing for the NodeJsScan scanner. Set to true to disable Babel processing. Introduced in GitLab 13.2.
SAST_FLAWFINDER_LEVEL 1 Ignore Flawfinder vulnerabilities under given risk level. Integer, 0=No risk, 5=High risk.
SAST_GITLEAKS_ENTROPY_LEVEL 8.0 Minimum entropy for secret detection. Float, 0.0 = low, 8.0 = high.
SAST_GOSEC_LEVEL 0 Ignore Gosec vulnerabilities under given confidence level. Integer, 0=Undefined, 1=Low, 2=Medium, 3=High.
SAST_GITLEAKS_COMMIT_FROM The commit a Gitleaks scan starts at.
SAST_GITLEAKS_COMMIT_TO The commit a Gitleaks scan ends at.
SAST_GITLEAKS_HISTORIC_SCAN false Flag to enable a historic Gitleaks scan.

Docker-in-Docker orchestrator

The following variables configure the Docker-in-Docker orchestrator, and therefore are only used when the Docker-in-Docker mode is enabled.

Environment variable Default value Description
SAST_ANALYZER_IMAGES Comma-separated list of custom images. Default images are still enabled. Read more about customizing analyzers.
SAST_PULL_ANALYZER_IMAGES 1 Pull the images from the Docker registry (set to 0 to disable). Read more about customizing analyzers.
SAST_DOCKER_CLIENT_NEGOTIATION_TIMEOUT 2m Time limit for Docker client negotiation. Timeouts are parsed using Go's ParseDuration. Valid time units are ns, us (or µs), ms, s, m, h. For example, 300ms, 1.5h or 2h45m.
SAST_PULL_ANALYZER_IMAGE_TIMEOUT 5m Time limit when pulling the image of an analyzer. Timeouts are parsed using Go's ParseDuration. Valid time units are ns, us (or µs), ms, s, m, h. For example, 300ms, 1.5h or 2h45m.
SAST_RUN_ANALYZER_TIMEOUT 20m Time limit when running an analyzer. Timeouts are parsed using Go's ParseDuration. Valid time units are ns, us (or µs), ms, s, m, h. For example, 300ms, 1.5h or 2h45m.

Analyzer settings

Some analyzers can be customized with environment variables.

Environment variable Analyzer Description
SCAN_KUBERNETES_MANIFESTS Kubesec Set to "true" to scan Kubernetes manifests.
KUBESEC_HELM_CHARTS_PATH Kubesec Optional path to Helm charts that helm will use to generate a Kubernetes manifest that kubesec will scan. If dependencies are defined, helm dependency build should be ran in a before_script to fetch the necessary dependencies. 
KUBESEC_HELM_OPTIONS Kubesec Additional arguments for the helm executable.
COMPILE SpotBugs Set to false to disable project compilation and dependency fetching. Introduced in GitLab 13.1.
ANT_HOME SpotBugs The ANT_HOME environment variable.
ANT_PATH SpotBugs Path to the ant executable.
GRADLE_PATH SpotBugs Path to the gradle executable.
JAVA_OPTS SpotBugs Additional arguments for the java executable.
JAVA_PATH SpotBugs Path to the java executable.
SAST_JAVA_VERSION SpotBugs Which Java version to use. Supported versions are 8 and 11. Defaults to 8.
MAVEN_CLI_OPTS SpotBugs Additional arguments for the mvn or mvnw executable.
MAVEN_PATH SpotBugs Path to the mvn executable.
MAVEN_REPO_PATH SpotBugs Path to the Maven local repository (shortcut for the maven.repo.local property).
SBT_PATH SpotBugs Path to the sbt executable.
FAIL_NEVER SpotBugs Set to 1 to ignore compilation failure.
SAST_GOSEC_CONFIG Gosec Path to configuration for Gosec (optional).
PHPCS_SECURITY_AUDIT_PHP_EXTENSIONS phpcs-security-audit Comma separated list of additional PHP Extensions.
SEARCH_MAX_DEPTH any Maximum number of directories traversed when searching for source code files. Default: 4.

Custom environment variables

Introduced in GitLab Ultimate 12.5.

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

CAUTION: Caution: Variables having names starting with these prefixes will not be propagated to the SAST Docker container and/or analyzer containers: DOCKER_, CI, GITLAB_, FF_, HOME, PWD, OLDPWD, PATH, SHLVL, HOSTNAME.

Reports JSON format

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

Here's an example SAST report:

{
  "version": "2.0",
  "vulnerabilities": [
    {
      "id": "9e96e0ab-23da-4d7d-a09e-0acbaa5e83ca",
      "category": "sast",
      "name": "Predictable pseudorandom number generator",
      "message": "Predictable pseudorandom number generator",
      "description": "The use of java.util.Random is predictable",
      "severity": "Medium",
      "confidence": "Medium",
      "scanner": {
        "id": "find_sec_bugs",
        "name": "Find Security Bugs"
      },
      "location": {
        "file": "groovy/src/main/groovy/com/gitlab/security_products/tests/App.groovy",
        "start_line": 47,
        "end_line": 47,
        "class": "com.gitlab.security_products.tests.App",
        "method": "generateSecretToken2",
        "dependency": {
          "package": {}
        }
      },
      "identifiers": [
        {
          "type": "find_sec_bugs_type",
          "name": "Find Security Bugs-PREDICTABLE_RANDOM",
          "value": "PREDICTABLE_RANDOM",
          "url": "https://find-sec-bugs.github.io/bugs.htm#PREDICTABLE_RANDOM"
        },
        {
          "type": "cwe",
          "name": "CWE-330",
          "value": "330",
          "url": "https://cwe.mitre.org/data/definitions/330.html"
        }
      ]
    },
    {
      "id": "e6dbf91f-4c07-46f7-a365-0169489c27d1",
      "category": "sast",
      "message": "Probable insecure usage of temp file/directory.",
      "severity": "Medium",
      "confidence": "Medium",
      "scanner": {
        "id": "bandit",
        "name": "Bandit"
      },
      "location": {
        "file": "python/hardcoded/hardcoded-tmp.py",
        "start_line": 10,
        "end_line": 10,
        "dependency": {
          "package": {}
        }
      },
      "identifiers": [
        {
          "type": "bandit_test_id",
          "name": "Bandit Test ID B108",
          "value": "B108",
          "url": "https://docs.openstack.org/bandit/latest/plugins/b108_hardcoded_tmp_directory.html"
        }
      ]
    },
  ],
  "remediations": []
}

Secret detection

Learn more about Secret Detection.

Security Dashboard

The Security Dashboard is a good place to get an overview of all the security vulnerabilities in your groups, projects and pipelines. Read more about the Security Dashboard.

Interacting with the vulnerabilities

Once a vulnerability is found, you can interact with it. Read more on how to interact with the vulnerabilities.

Vulnerabilities database

Vulnerabilities contained within the vulnerability database can be searched and viewed at the GitLab vulnerability advisory database.

Vulnerabilities database update

For more information about the vulnerabilities database update, check the maintenance table.

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:

NOTE: Note: 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. GitLab Runner's 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/gitlab-org/security-products/analyzers/bandit:2
registry.gitlab.com/gitlab-org/security-products/analyzers/brakeman:2
registry.gitlab.com/gitlab-org/security-products/analyzers/eslint:2
registry.gitlab.com/gitlab-org/security-products/analyzers/flawfinder:2
registry.gitlab.com/gitlab-org/security-products/analyzers/gosec:2
registry.gitlab.com/gitlab-org/security-products/analyzers/kubesec:2
registry.gitlab.com/gitlab-org/security-products/analyzers/nodejs-scan:2
registry.gitlab.com/gitlab-org/security-products/analyzers/phpcs-security-audit:2
registry.gitlab.com/gitlab-org/security-products/analyzers/pmd-apex:2
registry.gitlab.com/gitlab-org/security-products/analyzers/secrets:2
registry.gitlab.com/gitlab-org/security-products/analyzers/security-code-scan:2
registry.gitlab.com/gitlab-org/security-products/analyzers/sobelow:2
registry.gitlab.com/gitlab-org/security-products/analyzers/spotbugs:2

The process for importing Docker images into a local offline Docker registry depends on your network security policy. Please consult your IT staff to find an accepted and approved process by which external resources can be imported or temporarily accessed. Note that these scanners are updated periodically with new definitions, so consider if you're able to make periodic updates yourself.

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

Set SAST CI job 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: 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.

Troubleshooting

Error response from daemon: error processing tar file: docker-tar: relocation error

This error occurs when the Docker version that runs the SAST job is 19.03.0. Consider updating to Docker 19.03.1 or greater. Older versions are not affected. Read more in this issue.