Building DevSecOps Pipeline with GitLab CI
Overview
GitLab provides an integrated DevSecOps platform that embeds security testing directly into the CI/CD pipeline. By leveraging GitLab's built-in security scanners---SAST, DAST, container scanning, dependency scanning, secret detection, and license compliance---teams can shift security left, catching vulnerabilities during development rather than post-deployment. GitLab Duo AI assists with false positive detection for SAST vulnerabilities, helping security teams focus on genuine issues.
When to Use
- When deploying or configuring building devsecops pipeline with gitlab ci capabilities in your environment
- When establishing security controls aligned to compliance requirements
- When building or improving security architecture for this domain
- When conducting security assessments that require this implementation
Prerequisites
- GitLab Ultimate license (required for full security scanner suite)
- GitLab Runner configured (shared or self-hosted)
.gitlab-ci.yml pipeline configuration familiarity- Docker-in-Docker (DinD) or Kaniko for container builds
- Application deployed to a staging environment for DAST scanning
Core Security Scanning Stages
Static Application Security Testing (SAST)
SAST analyzes source code for vulnerabilities before compilation. GitLab supports 14+ languages using analyzers such as Semgrep, SpotBugs, Gosec, Bandit, and NodeJsScan. The simplest inclusion uses GitLab's managed templates.
Dynamic Application Security Testing (DAST)
DAST tests running applications by simulating attack payloads against HTTP endpoints. It detects XSS, SQLi, CSRF, and other runtime vulnerabilities that static analysis cannot find. DAST requires a deployed, accessible target URL.
Container Scanning
Uses Trivy to scan Docker images for known CVEs in OS packages and application dependencies. Runs after the Docker build stage to gate images before they reach a registry.
Dependency Scanning
Inspects dependency manifests (package.json, requirements.txt, pom.xml, Gemfile.lock) for known vulnerable versions. Operates at the source code level, complementing container scanning.
Secret Detection
Scans commits for accidentally committed credentials, API keys, tokens, and private keys using pattern matching and entropy analysis. Runs on every commit to prevent secrets from reaching the repository.
Implementation
Complete Pipeline Configuration
stages:
- build
- test
- security
- deploy-staging
- dast
- deploy-production
variables:
DOCKER_IMAGE: $CI_REGISTRY_IMAGE:$CI_COMMIT_SHORT_SHA
SECURE_LOG_LEVEL: "info"
include:
- template: Security/SAST.gitlab-ci.yml
- template: Security/Secret-Detection.gitlab-ci.yml
- template: Security/Dependency-Scanning.gitlab-ci.yml
- template: Security/Container-Scanning.gitlab-ci.yml
- template: DAST.gitlab-ci.yml
- template: Security/License-Scanning.gitlab-ci.yml
build:
stage: build
image: docker:24.0
services:
- docker:24.0-dind
variables:
DOCKER_TLS_CERTDIR: "/certs"
script:
- docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
- docker build -t $DOCKER_IMAGE .
- docker push $DOCKER_IMAGE
rules:
- if: $CI_COMMIT_BRANCH
unit-tests:
stage: test
image: $DOCKER_IMAGE
script:
- npm ci
- npm run test:coverage
coverage: '/Lines\s*:\s*(\d+\.?\d*)%/'
artifacts:
reports:
junit: junit-report.xml
coverage_report:
coverage_format: cobertura
path: coverage/cobertura-coverage.xml
sast:
stage: security
variables:
SAST_EXCLUDED_PATHS: "spec,test,tests,tmp,node_modules"
SEARCH_MAX_DEPTH: 10
container_scanning:
stage: security
variables:
CS_IMAGE: $DOCKER_IMAGE
CS_SEVERITY_THRESHOLD: "HIGH"
dependency_scanning:
stage: security
secret_detection:
stage: security
license_scanning:
stage: security
deploy-staging:
stage: deploy-staging
image: bitnami/kubectl:latest
script:
- kubectl set image deployment/app app=$DOCKER_IMAGE -n staging
- kubectl rollout status deployment/app -n staging --timeout=300s
environment:
name: staging
url: https://staging.example.com
rules:
- if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
dast:
stage: dast
variables:
DAST_WEBSITE: https://staging.example.com
DAST_FULL_SCAN_ENABLED: "true"
DAST_BROWSER_SCAN: "true"
needs:
- deploy-staging
rules:
- if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
deploy-production:
stage: deploy-production
image: bitnami/kubectl:latest
script:
- kubectl set image deployment/app app=$DOCKER_IMAGE -n production
- kubectl rollout status deployment/app -n production --timeout=300s
environment:
name: production
url: https://app.example.com
when: manual
rules:
- if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
Security Approval Policies
Configure scan execution policies to enforce mandatory security scans:
- Navigate to Security & Compliance > Policies
- Create a "Scan Execution Policy" requiring SAST and secret detection on all branches
- Create a "Merge Request Approval Policy" requiring security team approval when critical vulnerabilities are detected
Custom SAST Ruleset Configuration
Create .gitlab/sast-ruleset.toml to customize analyzer behavior:
[semgrep]
[[semgrep.ruleset]]
dirs = ["src"]
[[semgrep.passthrough]]
type = "url"
target = "/sgrep-rules/custom-rules.yml"
value = "https://semgrep.dev/p/owasp-top-ten"
[[semgrep.passthrough]]
type = "url"
target = "/sgrep-rules/java-rules.yml"
value = "https://semgrep.dev/p/java"
Security Dashboard and Vulnerability Management
Vulnerability Report
GitLab consolidates all scanner findings into a single Vulnerability Report accessible at Security & Compliance > Vulnerability Report. Each vulnerability includes:
- Severity rating (Critical, High, Medium, Low, Info)
- Scanner source (SAST, DAST, Container, Dependency, Secret)
- Location in source code or image layer
- Remediation guidance and suggested fixes
- Status tracking (Detected, Confirmed, Dismissed, Resolved)
Merge Request Security Widget
Every merge request displays a security scanning widget showing:
- New vulnerabilities introduced by the MR
- Fixed vulnerabilities resolved by the MR
- Comparison against the target branch baseline
Pipeline Optimization
- Parallel execution: Security scanners run concurrently in the security stage
- Caching: Use CI cache for dependency downloads to speed up scanning
- Incremental scanning: SAST can scan only changed files using
SAST_INCREMENTAL: "true"
- Fail conditions: Set
allow_failure: false on critical scanners to enforce quality gates
Monitoring and Metrics
| Metric | Description | Target |
|---|
| Pipeline security coverage | Percentage of projects with all scanners enabled | > 95% |
| Critical vulnerability MTTR | Time from detection to resolution for critical findings | < 48 hours |
| False positive rate | Percentage of dismissed-as-false-positive findings | < 15% |
| Secret detection block rate | Percentage of secret commits blocked by push rules | > 99% |
References
