Penetration Testing

From a penetration tester’s perspective, SQL Injection (SQLi) remains one of the most critical attack vectors against web applications. Among these, “UNION-based SQL injection”—which exploits the UNION operator—is a powerful technique that allows attackers to directly extract arbitrary information from within the database. In this article, we’ll explain how attackers subvert the specification of UNION to compromise systems, and discuss robust countermeasures against it from a design level. The Basics of UNION and Attack Prerequisites Fundamentally, the UNION operator is used to combine the results of two or more SELECT statements into a single result set. For example, it is used when you want to list both customer and employee data together. ...

SQL injection remains one of the most dangerous web application vulnerabilities, responsible for 33% of all web breaches in 2023. This comprehensive guide explains how these attacks work, their real-world impact, and effective defense strategies for developers and security professionals. 1. Understanding SQL Injection Attacks 1.1 What is SQL Injection? SQL injection occurs when attackers exploit improper input sanitization to inject malicious SQL code into database queries. This vulnerability allows attackers to: ...