Security testing is a crucial component for identifying security weaknesses and protecting your organisation against cyberattacks.
However, ‘security testing’ poses as an umbrella term for a variety of assessment methods; the two most essential are vulnerability assessments and penetration testing.
But what exactly is the difference between vulnerability assessments and penetration testing? Understanding the difference can be hugely beneficial in choosing an approach best tailored to your security needs.
In this blog, we’ll uncover the key differences between vulnerability assessments and penetration testing, as well as optimal instances for both, and how security testing can support you in achieving regulatory compliance.
What is a Vulnerability Assessment?
A vulnerability assessment is a process of identifying and assessing security vulnerabilities in networks, apps, clouds, and IT systems.
Vulnerability assessments identify weaknesses before attackers do, taking a proactive stance to prevent exploitation and data breaches before they can cause real damage.
Typically, these weaknesses are identified using vulnerability scanning tools. These tools help businesses identify thousands of vulnerabilities from anywhere between a few minutes to several hours, depending on the size of the attack surface.
After the vulnerability scan is complete, most vulnerability assessment tools will provide a report of the weaknesses identified. You can either run these assessments manually or on a scheduled basis.
What is Penetration Testing?
Penetration testing is a more thorough approach to security assessment, though it is also slightly more time-consuming. Pentesting simulates real-world attacks in a controlled environment to evaluate the strength of your business’s security posture against real cyber attacks.
Pentesting differs based on the needs of your business. From mobile application testing to cloud security testing, every organisation has different priorities and areas that need assessment.
Having testers emulate the role of attackers helps businesses understand how real-world hackers may identify vulnerabilities. Similar to vulnerability assessments, pentesting enables the remediation of security gaps before real cyber attacks occur.
However, penetration testing uses more nuance and business logic to exploit vulnerabilities, providing more thorough and complex security insights than vulnerability testing alone.
Role of Penetration Testers
Performing these penetration tests will be penetration testers- a dedicated team of security professionals, otherwise known as ethical hackers.
Pentesters can:
- Simulate real-world attacks using ethical hacking techniques to identify and exploit security vulnerabilities.
- Provide detailed reports on vulnerabilities and remediation efforts.
- Provide complex insights into how your business can improve its security posture.
- Have in-depth knowledge of security vulnerabilities and exploit techniques.
More experienced penetration testing vendors will demonstrate CREST-accreditation- certification to prove that the testing is complete with the highest quality and regularly audited.
Look for CREST-accredited vendors, like OnSecurity, when booking a test. Many security professionals will also have a list of their accreditations and experience available for review, which can be beneficial when choosing a vendor best aligned with the required testing type.
Penetration Tests and Compliance
Penetration testing is great for helping businesses meet compliance requirements by proving that their security controls work in real attack scenarios.
Many regulations, such as PCI DSS and ISO27001, require regular penetration tests to ensure organisations maintain strong security standards. These tests identify and validate vulnerabilities, enabling timely remediation and minimising the potential havoc of critical vulnerabilities going unchecked.
Key Differences Between Vulnerability Assessment and Penetration Testing
| Aspect | Vulnerability Assessment | Penetration Testing |
|---|---|---|
| Purpose | Finds and reports flaws without exploiting them. | Exploits vulnerabilities to show real impact. |
| Scope | Broad, covering many systems. | Targeted, focusing on selected areas. |
| Frequency | Regular or ongoing. | Periodic (e.g., yearly or after changes). |
| Method | Mostly automated scanning. | Mostly manual testing, with automated supplementation |
| Outcome | List of known security weaknesses. | Proof of what can be exploited. |
| Role | Maintains overall security visibility against potential vulnerabilities. | Demonstrates real-world risk, provides more complex insights for your internal security team. |
Risk Assessment and Management
Before choosing between a vulnerability assessment and a penetration test, it’s important to consider your organisation’s overall risk picture. Risk assessment helps you understand which systems matter most, where potential threats lie, and what impact a security issue could have.
Vulnerability assessments and penetration testing both support this process. Vulnerability assessments highlight weaknesses that need attention, while penetration testing shows how serious those weaknesses could be if exploited.
Together, they help your team prioritise remediation and make informed decisions about where to focus security efforts.
When to Use Vulnerability Assessment vs Penetration Testing?
Using the table above may give you an idea of which security assessment approach could be optimal for your organisation. However, if you’re still uncertain, here are some general rules of thumb to help you determine which best suits your security needs.
Vulnerability Assessments
- Best for regular, surface-level security checks and ongoing risk management.
- Use vulnerability assessment for regular security checks and ongoing risk management.
- Ideal for discovering unknown vulnerabilities before attackers do.
- Suitable for broad scans across networks, applications, and cloud environments.
Penetration Testing
- Penetration testing is used to understand the real-world impact of security vulnerabilities.
- Test defences more thoroughly against skilled and simulated malicious attackers.
- Provides evidence of a more intrinsic commitment to security to vendors and regulatory boards.
The Takeaway: Better Together!
While vulnerability assessments and penetration testing each provide valuable insights, they are most effective when used together. Vulnerability assessments provide you with regular visibility into potential weaknesses, helping you stay on top of emerging risks. Penetration testing then takes this a step further by showing how those weaknesses could be exploited in real-world scenarios.
By combining both approaches, organisations gain a clearer, more confident understanding of their security posture. This not only strengthens everyday defences but also supports compliance, informed decision-making, and long-term risk management.
In short, vulnerability assessments help you find the cracks, and penetration testing simulates what happens if someone tries to break through them. Using both ensures your organisation stays one step ahead.
Revolutionise your organisation’s approach to cybersecurity with OnSecurity. Our consultative, platform-based pentesting supports by identifying existing vulnerabilities and cyber risks in your security strategy, laying the foundations for effective remediations in your workplace.
