SAST Configuration

Static Application Security Testing (SAST) tool setup, configuration, and custom rule creation for comprehensive security scanning across multiple programming languages.

Overview

This skill provides comprehensive guidance for setting up and configuring SAST tools including Semgrep, SonarQube, and CodeQL. Use this skill when you need to:

• Set up SAST scanning in CI/CD pipelines

• Create custom security rules for your codebase

• Configure quality gates and compliance policies

• Optimize scan performance and reduce false positives

• Integrate multiple SAST tools for defense-in-depth

Core Capabilities

1. Semgrep Configuration

• Custom rule creation with pattern matching

• Language-specific security rules (Python, JavaScript, Go, Java, etc.)

• CI/CD integration (GitHub Actions, GitLab CI, Jenkins)

• False positive tuning and rule optimization

• Organizational policy enforcement

2. SonarQube Setup

• Quality gate configuration

• Security hotspot analysis

• Code coverage and technical debt tracking

• Custom quality profiles for languages

• Enterprise integration with LDAP/SAML

3. CodeQL Analysis

• GitHub Advanced Security integration

• Custom query development

• Vulnerability variant analysis

• Security research workflows

• SARIF result processing

Quick Start

Initial Assessment

• Identify primary programming languages in your codebase

• Determine compliance requirements (PCI-DSS, SOC 2, etc.)

• Choose SAST tool based on language support and integration needs

• Review baseline scan to understand current security posture

Basic Setup

Semgrep quick start

pip install semgrep semgrep --config=auto --error

SonarQube with Docker

docker run -d --name sonarqube -p 9000:9000 sonarqube:latest

CodeQL CLI setup

gh extension install github/gh-codeql codeql database create mydb --language=python

Reference Documentation

• Semgrep Rule Creation - Pattern-based security rule development

• SonarQube Configuration - Quality gates and profiles

• CodeQL Setup Guide - Query development and workflows

Templates & Assets

• semgrep-config.yml - Production-ready Semgrep configuration

• sonarqube-settings.xml - SonarQube quality profile template

• run-sast.sh - Automated SAST execution script

Integration Patterns

CI/CD Pipeline Integration

GitHub Actions example

• name: Run Semgrep uses: returntocorp/semgrep-action@v1 with: config: >- p/security-audit p/owasp-top-ten

Pre-commit Hook

.pre-commit-config.yaml

• repo: https://github.com/returntocorp/semgrep rev: v1.45.0 hooks:
  • id: semgrep args: ['--config=auto', '--error']

Best Practices

Start with Baseline

• Run initial scan to establish security baseline

• Prioritize critical and high severity findings

• Create remediation roadmap

Incremental Adoption

• Begin with security-focused rules

• Gradually add code quality rules

• Implement blocking only for critical issues

False Positive Management

• Document legitimate suppressions

• Create allow lists for known safe patterns

• Regularly review suppressed findings

Performance Optimization

• Exclude test files and generated code

• Use incremental scanning for large codebases

• Cache scan results in CI/CD

Team Enablement

• Provide security training for developers

• Create internal documentation for common patterns

• Establish security champions program

Common Use Cases

New Project Setup

./scripts/run-sast.sh --setup --language python --tools semgrep,sonarqube

Custom Rule Development

See references/semgrep-rules.md for detailed examples

rules:

• id: hardcoded-jwt-secret pattern: jwt.encode($DATA, "...", ...) message: JWT secret should not be hardcoded severity: ERROR

Compliance Scanning

PCI-DSS focused scan

semgrep --config p/pci-dss --json -o pci-scan-results.json

Troubleshooting

High False Positive Rate

• Review and tune rule sensitivity

• Add path filters to exclude test files

• Use nostmt metadata for noisy patterns

• Create organization-specific rule exceptions

Performance Issues

• Enable incremental scanning

• Parallelize scans across modules

• Optimize rule patterns for efficiency

• Cache dependencies and scan results

Integration Failures

• Verify API tokens and credentials

• Check network connectivity and proxy settings

• Review SARIF output format compatibility

• Validate CI/CD runner permissions

Related Skills

• OWASP Top 10 Checklist

• Container Security

• Dependency Scanning

Tool Comparison

Tool Best For Language Support Cost Integration

Semgrep Custom rules, fast scans 30+ languages Free/Enterprise Excellent

SonarQube Code quality + security 25+ languages Free/Commercial Good

CodeQL Deep analysis, research 10+ languages Free (OSS) GitHub native

Next Steps

• Complete initial SAST tool setup

• Run baseline security scan

• Create custom rules for organization-specific patterns

• Integrate into CI/CD pipeline

• Establish security gate policies

• Train development team on findings and remediation