A system administrator sees the following URL in the webserver logs: Which action will mitigate against this attack?

SSL/TLS secures data confidentiality in transit but provides no protection against injection payloads that arrive over an encrypted channel and are processed by the application.

Base64 is a data encoding scheme, not a security sanitization mechanism, and does not prevent injected SQL characters from reaching and being interpreted by the database.

SQL injection succeeds when user-supplied data is concatenated into a database query without sanitization, allowing characters like single quotes and SQL keywords to alter query logic. Filtering or encoding potentially harmful characters on the server side - before input reaches the query engine - neutralizes the attack by ensuring user data is treated strictly as data, not as executable SQL syntax.

Requiring authentication controls who submits requests but does not validate or sanitize the content of those requests, so authenticated users can still submit malicious SQL payloads.