What is SQL Injection?

SQL Injection is a security vulnerability that allows attackers to manipulate a site's database queries by injecting malicious SQL through input fields or parameters.

Why is SQL Injection dangerous?

It can expose, modify, or delete sensitive data, escalate privileges, and compromise the entire application or backend database.

How can I prevent SQL Injection?

Use parameterized queries / prepared statements, validate and sanitize inputs, apply least-privilege on DB accounts, and use ORM or stored procedures where appropriate.

SQL Injection Interactive Demo

🔒 SQL Injection Attack Demo

The Problem: Directly inserting user input into SQL queries allows hackers to exploit vulnerabilities!

Username:

Password:

Server Log:

Waiting for a login attempt...

SQL Query Preview:
SELECT * FROM Users WHERE username = '?' AND password = '?';

🛡️ SQL Injection Prevention Methods

Solution: Use prepared statements and proper input validation to block SQL injection attacks.

// Prepared Statement Example (Safe)
const query = "SELECT * FROM Users WHERE username = ? AND password = ?";
db.prepare(query).get(username, hashedPassword);
// User input is automatically escaped

// Input Validation
function validateInput(input) {
  return input.replace(/['"\\;]/g, '');
  // Remove dangerous characters
}

Always use parameterized queries

Hash passwords with bcrypt or SHA-256

Validate all user inputs

Use ORM tools when possible

🔍 Vulnerable vs Secure Code Comparison

Aspect	❌ Vulnerable Code	✅ Secure Code
Query Building	String concatenation	Prepared statements
Input Handling	Direct insertion	Parameter binding
Password Storage	Plain text comparison	Hashed comparison
Risk Level	🔴 High (Full bypass)	🟢 Low (Attack blocked)