The Plain English Version

Penetration testing (pen testing) is hiring ethical hackers to try to break into your systems. They use the same techniques as real attackers to find vulnerabilities before criminals do.

Think of it like hiring a locksmith to try to break into your building. They will find the weak points and tell you how to fix them - before someone with bad intentions finds them first.

Pen Test vs Vulnerability Scan

Vulnerability scan: Automated tool that identifies known vulnerabilities. Quick and cheap but surface-level.

Penetration test: Human testers actively trying to exploit vulnerabilities and chain them together. Deeper but more expensive.

Types of Pen Tests

  • External - Testing internet-facing systems like websites and email
  • Internal - Testing from inside the network (what if an attacker gets in?)
  • Web application - Focused testing of specific applications
  • Social engineering - Testing human vulnerabilities (phishing simulations)
  • Physical - Attempting to gain physical access to facilities

When Do You Need One?

Annual pen tests are becoming standard practice. You should also test after significant changes to your infrastructure, before launching new applications, when compliance requires it, and after security incidents to verify fixes.

Some frameworks (PCI DSS, DORA) mandate regular penetration testing. Cyber Essentials Plus includes a basic technical verification.

Getting Value from Pen Tests

A pen test is only valuable if you act on the findings. Before commissioning one, ensure you have budget and resources to remediate what they find. A report gathering dust helps nobody.

Choose testers with relevant certifications (CREST, CHECK, OSCP) and experience in your industry. Get references and sample reports.