CyberTech Inc. recently experienced SQL injection attacks on its official website. The company appointed Bob, a security professional, to build and incorporate defensive strategies against such…

Output encoding transforms data when it is rendered to prevent injection in the output context such as HTML or JavaScript, but it does not validate or restrict the incoming input values before processing.

Enforcing least privileges limits the database account permissions to reduce the impact of a successful attack, but it does not prevent malicious input from being submitted or processed.

Whitelist validation defines an explicit set of approved inputs - including acceptable data types, value ranges, sizes, and formats - and rejects any input that does not conform to these approved criteria. This is highly effective against SQL injection because malicious SQL metacharacters and payloads are not in the approved list and are therefore blocked before reaching the database layer. It is a proactive defense that assumes all input is untrusted unless it matches a known-good pattern.

Blacklist validation attempts to block known bad characters or patterns and is weaker than whitelisting because attackers can encode or obfuscate payloads to bypass the blocked list.