Overview
This lecture covers SQL injection attacks, how they work, their dangers, and demonstrates a practical example of exploiting an application vulnerable to such attacks.
Authentication and Application Security
- Applications require authentication (username and password) to provide user-specific data access.
- Attackers may inject malicious code to bypass authentication and access all database data.
SQL Injection Attacks
- SQL injection is a technique where attackers insert malicious SQL code into application inputs to manipulate database queries.
- Lack of proper input validation by developers leaves applications vulnerable to SQL injection.
- Other types of code injection include HTML, XML, and LDAP.
How SQL Injection Works
- SQL (Structured Query Language) is used for managing data in relational databases like MySQL or SQL Server.
- Improperly handled user input can let attackers modify SQL commands to bypass authentication.
- Example: Query
SELECT * FROM users WHERE name = 'professor' can be altered to always return true with input like ' OR '1'='1'.
- This injection makes the query return all user data, circumventing security controls.*
Demonstration Example
- Tools like WebGoat provide intentionally vulnerable applications for practicing SQL injection.
- Example login: normal user inputs are username "Smith" and TAN "3SL99A".
- Attacker injects
' OR 1=1;-- as the username to retrieve all records instead of just their own.
- Successful injection exposes all user IDs, names, departments, salaries, and authentication data.
Key Terms & Definitions
- Authentication — Verifying a user’s identity before granting application access.
- SQL (Structured Query Language) — Language for managing and querying data in relational databases.
- SQL Injection — Attack technique where malicious SQL code is inserted into application input fields to manipulate database queries.
- Input Validation — Process of verifying and cleaning user inputs to prevent malicious data from being processed.
Action Items / Next Steps
- Review methods for secure input handling and validation in application development.
- Practice preventing SQL injection vulnerabilities using parameterized queries or prepared statements.
- Complete any assigned reading on database security fundamentals.