Whitelist Validation
Whitelist validation is a security and data validation technique where only pre-approved, known-good inputs are allowed, while all others are rejected by default. It is commonly used in software development to prevent injection attacks, enforce data integrity, and ensure that user inputs conform to expected formats. This approach contrasts with blacklist validation, which blocks known-bad inputs but may miss new or unknown threats.
Developers should use whitelist validation in scenarios requiring high security or strict data control, such as web form inputs, API parameter validation, and file upload handling, to mitigate risks like SQL injection, cross-site scripting (XSS), and command injection. It is particularly valuable in applications processing sensitive data or operating in regulated environments, as it reduces the attack surface by explicitly defining acceptable inputs rather than trying to anticipate all malicious ones.