Which of the following tools performs comprehensive tests against web servers, including dangerous files and CGIs?

Dsniff is a collection of network sniffing and credential-capturing tools focused on passive traffic interception, not active web server scanning.

John the Ripper is a password-cracking tool that performs dictionary and brute-force attacks against password hashes, not web server vulnerability assessments.

Snort is a network intrusion detection and prevention system that inspects traffic for known attack signatures, not a tool that actively probes web servers for vulnerabilities.

Nikto performs comprehensive web server assessments including checks for over 6,700 potentially dangerous files and CGIs, outdated server versions, and version-specific vulnerabilities. It is purpose-built for web server enumeration and vulnerability identification, directly matching the question's description of testing against dangerous files and CGIs. Unlike general-purpose tools, Nikto targets the HTTP layer and web application surface.