What is a Pentest?
A pentest (short for penetration test) is a controlled, ethical hacking attempt in which a security professional tests the security of systems, networks or applications by looking for vulnerabilities that a real attacker could exploit.
The aim is to identify weaknesses before malicious actors do — and to provide recommendations for fixing them.
🔍 What is tested?
A penetration test can target various domains:
- Network (internal or external)
- Web applications / APIs
- Mobile apps
- Industrial systems (e.g. SCADA, PLC)
- Cloud environments
- Active Directory
- Social engineering (e.g. Phishing)
🔧 Test types
| Type of pentest | Description |
|---|---|
| Black box | Tester knows nothing in advance; simulates an external attacker |
| White box | Tester has full information about the environment; in-depth and structured |
| Grey box | Tester has limited information (e.g. user privileges); a realistic simulation |
| Red Teaming | Advanced, long-running test including stealth and detection evaluation |
🛠 Commonly used tools
- Nmap, Nessus, Burp Suite, Metasploit, Nikto
- Scripting in Python, Bash or PowerShell
- Specialist tools for OT testing (e.g. Modbus fuzzers)
✅ What does a pentest deliver?
- A report of the vulnerabilities found (classified by risk)
- Technical details and evidence of impact (e.g. screenshots, logs)
- Recommendations for mitigation or patching
- Insight into the effectiveness of existing security controls
- Support for compliance (e.g. ISO 27001, NIS2, IEC 62443)
⚠️ Important considerations
- Always carry out a pentest with prior authorisation (a legal context)
- Avoid production loss in OT environments; preferably test in a test environment
- Set a scope and time frame
- Combine pentests with continuous Vulnerability Management
📌 In summary
A penetration test is a simulated attack under controlled conditions to uncover vulnerabilities, understand risks and improve security. It is an important instrument within any Cybersecurity strategy.