What is penetration testing and how does it work?

Penetration testing (pen testing) is a simulated cyberattack against your systems, applications, or infrastructure, conducted by authorised security professionals. The goal is to identify vulnerabilities before real attackers do. Testers use the same techniques as malicious hackers, document everything they find, and provide a detailed report with remediation guidance.

How long does penetration testing take?

Duration depends on scope. A focused web application test typically takes 3–5 days, a network infrastructure assessment 5–10 days, and a comprehensive red team engagement can run for several weeks. We agree the scope and timeline upfront so there are no surprises.

What's the difference between penetration testing and vulnerability scanning?

Vulnerability scanning is an automated process that identifies known weaknesses. Penetration testing goes further — qualified professionals manually exploit those vulnerabilities (and others) to determine the real-world impact, chain together attack paths, and identify logic flaws that automated tools cannot detect.

How often should penetration testing be done?

Most security frameworks and compliance standards recommend at least annual penetration testing. Additionally, tests should be run after significant changes to infrastructure, following major software releases, and after any security incident. High-risk organisations benefit from more frequent or continuous testing programmes.

What certifications do your penetration testers have?

Our penetration testers hold leading industry certifications including CREST, OSCP (Offensive Security Certified Professional), CEH (Certified Ethical Hacker), CISSP, and CompTIA PenTest+. All work is conducted in strict compliance with our rules of engagement and relevant UK legislation.

What effects can penetration testing have on my systems?

Penetration testing is conducted carefully to minimise disruption. We agree on a rules of engagement document before testing begins, defining what systems can be tested, testing windows, and escalation procedures. Some tests may temporarily impact performance, so we typically schedule intensive testing during low-traffic periods.

What certifications or accreditation does a penetration tester hold?

Professional penetration testers should hold certifications like CREST, OSCP, CEH, or equivalent. HireProgrammer only works with certified, experienced professionals who comply with all relevant UK laws and ethical guidelines, including the Computer Misuse Act and the authorisation requirements for ethical hacking.