Updated
Short answer
A vulnerability scan is an automated tool that lists known weaknesses. A penetration test is a person, often helped by tools, actually trying to break in and proving what an attacker could reach. A red team exercise tests whether your people and defenses notice and stop a realistic attack aimed at a specific goal. Most small businesses should scan continuously, pen test at least yearly, and red team once they have a security team or provider to test.
Side by side
- Vulnerability scan: automated, hours, finds known issues, many false positives, low cost. Use it monthly or continuously.
- Penetration test: human-led, days to weeks, proves real impact by chaining issues, includes fixes and a retest. Use it yearly and after major changes.
- Red team: goal-based, weeks, tests detection and response across people, systems and AI tools. Use it once basic defenses are in place.
Where AI security testing fits
If your business uses AI chatbots, assistants or agents that can see data or take actions, they need their own testing. Scanners do not test for prompt injection or AI data leakage. An AI security test checks whether your AI tools can be tricked into revealing data or misusing the tools they can reach, which OWASP lists as top risks for LLM applications.
Which one do you need?
- An auditor, insurer or customer asked for a test: a penetration test with an attestation letter.
- You have never had a test: start with a penetration test of what is reachable from the internet.
- You use AI tools on customer data: add an AI and agent safety test.
- You have an IT provider and want proof they would catch an attack: a red team exercise.