Key points at a glance
- A pentest is an authorised, simulated attack on your systems to find vulnerabilities.
- Depending on scope, website, web applications, email, remote access and internal networks are tested.
- Without written authorisation from the system owner, a pentest is not permitted.
- The result is a report with prioritised vulnerabilities and concrete recommendations.
What is a pentest?
A pentest, short for penetration test, is a simulated hacker attack on your IT systems carried out with your explicit permission. The goal is to find security gaps before real attackers exploit them. Unlike an automated scan, a pentest combines different attack paths, as real attackers do.
Which types of pentests exist?
- External pentest: testing systems reachable from outside, such as website, mail server and remote access.
- Internal pentest: testing from the perspective of an attacker who is already inside the network.
- Web application pentest: targeted testing of login, forms, customer portals and interfaces.
- Black box, grey box, white box: with no, partial or full prior knowledge of the system.
How does a pentest work?
- Initial meeting: define goals, scope and period.
- Written authorisation: the owner of the systems approves the test.
- Information gathering: which systems are reachable and which software runs on them?
- Attack phase: vulnerabilities are searched for and exploited in a controlled way.
- Report: all findings, prioritised by risk, with recommendations.
- Fix and retest: close gaps and check that they are really closed.
Why authorisation is so important
Attacking third-party systems without permission is a criminal offence. A serious pentest therefore always starts with written authorisation from the system owner, with a defined scope and period. Make sure every provider checks your authorisation.
What does a pentest cost?
Costs depend on the scope: how many systems are tested, how deeply, and is documentation needed for audits, insurers or certifications? A basic test of externally reachable systems is considerably cheaper than a comprehensive test including internal networks and web applications.
How often should you test?
At least after major changes to systems and regularly, for example annually. Article 32 of the GDPR requires a process for regularly testing security measures, and for companies covered by NIS2, regular testing is part of risk management.
Conclusion
A pentest makes visible where your company is vulnerable and delivers concrete steps for fixing it. With clear authorisation, a defined scope and an understandable report, it becomes one of the most effective building blocks of your IT security.
Frequently asked questions
AIErdinc Dincdemir
Sales, business development and project management at Optivanta
This article is for general information only and does not constitute legal, tax or investment advice. It does not replace advice on your individual case. Despite careful research, we accept no liability for accuracy, completeness or timeliness; use is at your own risk. Articles bearing an author's name reflect that author's opinion. The provider of and party responsible for all content is Optivanta Solutions LLC. More in the imprint
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