SQL Injection

SQL Injection is a critical vulnerability that occurs when an application fails to properly validate user input before incorporating it into SQL queries. This attack technique allows malicious actors to manipulate database operations by inserting malicious SQL code into input fields.\n\nWhen a web application constructs SQL statements dynamically using user-supplied data but lacks proper sanitization, attackers can inject commands that alter the query's intended behavior. For example, if a login form creates a query like 'SELECT * FROM users WHERE username='"+username+"' AND password='"+password+"'', an attacker might input: username: admin' -- which effectively comments out the password check, potentially granting unauthorized access.\n\nCommon SQL Injection attacks include:\n\n1. Error-based: Forcing the database to generate error messages revealing structural information\n2. Union-based: Using UNION operators to combine results from injected queries with original queries\n3. Blind SQL Injection: Inferring database information through true/false questions when no output is visible\n4. Time-based: Detecting successful injections by causing deliberate time delays in responses\n\nTo protect against SQL Injection, ethical hackers recommend:\n\n- Implementing parameterized queries/prepared statements\n- Using stored procedures with sanitized inputs\n- Applying input validation and sanitization\n- Employing least privilege database accounts\n- Regular security testing and code reviews\n- Web Application Firewalls (WAF) as an additional layer of protection\n\nSQL Injection remains prevalent in OWASP Top 10 security risks because it can lead to unauthorized data access, data modification, deletion of information, and even complete system compromise. For ethical hackers, understanding this attack is essential for properly assessing application security and helping organizations protect their valuable data assets.

SQL Injection is a critical vulnerability that occurs when an application fails to properly validate user input before incorporating it into SQL queries. This attack technique allows malicious actors…

Concepts covered: SQL Injection Concepts, Types of SQL Injection, SQL Injection Methodology, SQL Injection Tools, Evasion Techniques, SQL Injection Countermeasures