Which of the following is NOT considered a database vulnerability?

Data encryption is a security measure rather than a vulnerability. It serves to protect data from unauthorized access by converting it into a format that is unreadable without the appropriate decryption key. Encryption is an essential component of a comprehensive security strategy, particularly for databases, as it helps safeguard sensitive information.

In contrast, design flaws, capacity issues, and unauthorized activity by authorized users are considered vulnerabilities. Design flaws could involve inadequacies in how the database schema is structured, potentially leading to data integrity issues or performance problems. Capacity issues refer to a database's inability to handle its workload or growth, which can lead to slow performance and operational disruptions. Unauthorized activity by authorized users highlights risks associated with user privileges and access control, where individuals may misuse their privileges to compromise data integrity or confidentiality.

Recognizing the distinction between security measures, like encryption, and vulnerabilities is crucial for effective database security management.