Your question is OWASP Top 10 Web Security. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Interviewer covered OWASP TOP 10 with web application security vulnerabilities.
Explain the major vulnerability classes, how an attacker exploits them, and the controls you would apply. Include practical examples, detection methods, and how you would validate remediation.