Applying Checkov to Terraform as Code – A TFSEC Alternative

Static Application Security Testing (SAST) is a critical practice in modern DevSecOps. While tools like SonarQube, Snyk, and Veracode are popular, this article focuses on GitHub CodeQL – a semantic code analysis engine that treats code as a database. We will apply it to a vulnerable Java Spring Boot application to detect SQL Injection and Path Traversal. 🤔 Why CodeQL? Unlike pattern-based scanners, CodeQL builds a relational database of your code, including abstract syntax trees, control flow graphs, and data flow graphs. This allows it to track tainted data across functions, classes, and files, drastically reducing false positives. 🚨 Target Application (Vulnerable Java App) Let's look at a simple REST API with two vulnerable endpoints. File: UserController.java package com.demo.controller ; import com.demo.model.User ; import org.springframework.beans.factory.annotation.Autowired ; import org.springframework.jdbc.core.JdbcTemplate ; import org.springframework.web.bind.annotation.* ; import java.nio.file.Files ; import java.nio.file.Paths ; import java.util.List ; @RestController @RequestMapping ( "/api" ) public class UserController { @Autowired private JdbcTemplate jdbcTemplate ; // Vulnerability 1: SQL Injection @GetMapping ( "/users" ) public List < User > getUsers ( @RequestParam ( "id" ) String userId ) { String sql = "SELECT * FROM users WHERE id = " + userId ; // Dangerous concatenation return jdbcTemplate . query ( sql , ( rs , rowNum ) -> new User ( rs . getString ( "id" ), rs . getString ( "name" ))); } // Vulnerability 2: Path Traversal @GetMapping ( "/file" ) public String readFile ( @RequestParam ( "filename" ) String filename ) throws Exception { return new String ( Files . readAllBytes ( Paths . get ( "/var/data/" + filename ))); } } 🛠️ Installing and Configuring CodeQL CLI You can run CodeQL locally to analyze your code before pushing it to a repository. 1. Download CodeQL from GitHub releases: wget [ https://github.com/github/codeql-cli-binaries/re