Mitigating SQL Injection Attacks: A Comprehensive Study on Attack Vectors, Classification, and Prevention Techniques

SQL Injection (SQLi) is a severe and widely exploited security vulnerability in web applicationsthat enables attackers to manipulate backend databases through maliciously crafted input. Thisattack compromises the confidentiality, integrity, and availability of data by allowing unauthorizedaccess, data leakage, and even complete system takeover. SQL Injection remains one of the topthreats listed in the OWASP Top 10 due to persistent flaws in input validation and query handling.This paper provides a detailed classification of SQL Injection attacks, including Classic SQLInjection, Blind SQL Injection (Boolean-based and Time-based), Error-based SQL Injection, andOut-of-Band SQL Injection. Each type exploits different system behaviors and levels of databaseexposure to achieve malicious goals. In response to these threats, the paper explores multiple prevention techniques such asparameterized queries (prepared statements), stored procedures, input validation and sanitization,the principle of least privilege, and deployment of Web Application Firewalls (WAF). It alsoemphasizes the importance of secure development practices, regular code audits, and adherence tosecurity standards like those provided by OWASP.