Pen Testing vs Vulnerability Scanning: The Key Differences & When to Use Each

When it comes to assessing your organisation’s cybersecurity, two methods often cause confusion: penetration testing (pen testing) and vulnerability scanning. This confusion has led to many businesses being sold a vulnerability scan under the guise of a pen test – potentially putting their networks, systems and applications at risk in the process.

Understanding the difference is crucial to protecting your business effectively.

Effective cyber security measures are as important as ever, especially with the recent bouts of ransomware attacks that have been widely reported in the media. Due to this, and the ongoing security of your business, it’s incredibly important to know the difference between a vulnerability scan and a penetration test – two very essential components of a comprehensive business security strategy – and knowing when to deploy each one for the best outcome.

Essentially, vulnerability scanning is like identifying that the door lock on your house is loose. The pen test works out how to break it to get into the house.

In this guide, we’ll dive into the differences between penetration testing vs vulnerability scanning, look at cost comparisons and best practices for both and share how you can decide which to deploy for your specific business requirements.

Understanding Cyber Security Assessments

As cyber threats become increasingly sophisticated, businesses must adopt proactive strategies to mitigate these risks effectively. Security assessments, like vulnerability scanning and penetration testing, play an essential role in identifying your potential security weaknesses – before a cybercriminal can.

Vulnerability scanning and penetration testing might seem similar, but they serve distinctly different purposes and vary significantly in their approach, depth, and outcomes.

Why Security Testing is Essential for Businesses

The rising sophistication and frequency of cyberattacks, such as ransomware, phishing, and zero-day exploits, not to mention the rising threat of AI-powered attacks, underscore the need for regular and comprehensive security testing.

Unpatched vulnerabilities can become critical security gaps in your infrastructure, leaving your organisation susceptible to attacks that could cause financial loss, data breaches, and significant reputational damage.

Regular security testing not only addresses technical weaknesses but also supports compliance with regulations such as ISO 27001, PCI DSS, and industry specific mandates such as DORA and NIS2.

The Role of Penetration Testing and Vulnerability Scanning in Cyber Security Strategy

While both methods aim to identify gaps and strengthen security, their roles are different and complementary. Vulnerability scanning provides rapid, scalable assessments, highlighting potential weaknesses against known Common Vulnerabilities and Exposures (CVEs).

Pen testing offers deeper insights, using ethical hackers to simulate real world cyberattacks, demonstrating exactly how a malicious hacker would break into your infrastructure and the tangible impacts of these identified vulnerabilities.

What is Vulnerability Scanning?

Vulnerability scanning involves automated tools designed to detect known security weaknesses (CVEs) across IT systems, quickly.

How Automated Vulnerability Scanners Work

Automated scanners rapidly identify security weaknesses by running through a scripted method to match system configurations against extensive databases of known vulnerabilities.

These scans can quickly highlight outdated software, unpatched systems, and common misconfigurations. If there is a flaw in software or misconfigured assets, the vulnerability scan is very likely to pick up on it. After the scan, you will receive a report on the findings. This will normally include how severe any vulnerabilities found are, categorised as critical, high, etc, and perhaps even a simple outline for how to fix them, depending on the provider you’re working with.

Common Tools Used for Vulnerability Scanning

Popular scanners include Nessus, Qualys, and OpenVAS. Commercial tools offer extensive features suitable for enterprise environments, whereas opensource tools can provide a lighter and more cost effective alternative.

However, a number of organisations don’t have the resource to deploy vulnerability scanning software tooling, nor the expertise to fully interpret results and deploy the mitigation steps needed.

When working with an expert cyber security service provider for managed vulnerability scanning, ensure that the provider is using industry leading, and CREST approved, tooling to conduct your scans to ensure the best results.

Benefits of Vulnerability Scanning for Businesses

Vulnerability scanning is fast, cost effective, and easily integrated into your ongoing security operations. The results of a vulnerability scan provide a clear focus on where the technical vulnerabilities are within your organisation. With this information you can create a patch management plan to manage, understand and control the open vulnerabilities that could impact your business.

Regular scans enable your business to proactively identify and address vulnerabilities against known threat databases, maintaining baseline security standards.

All businesses should perform scans regularly, typically monthly, or whenever significant system change occurs such as new feature deployments in software systems or a migration of workloads to the cloud.

Limitations of Vulnerability Scanning

Despite its benefits of speed and protection against known threats, vulnerability scanning will miss potential vulnerabilities that can’t be identified with logic-based scanning and will generate a volume of false positives, which ideally require expert human verification.

Vulnerability scans provide breadth, not depth, highlighting potential issues against known threats without showing unknown attacks paths a hacker could take and without fully examining how infrastructure might be exploited.

What is Penetration Testing?

Penetration testing involves ethical hackers actively simulating cyberattacks to uncover exploitable security weaknesses.

A penetration test is completely different from a vulnerability scan – it provides a much more intensive and comprehensive report of the state of your security system. The process of penetration testing effectively begins as soon as the vulnerability scan ends – really delving into what could be wrong with your security system and finding out where it can be exploited.

How Manual Pen Testing Identifies Security Weaknesses

Manual pen testing simulates targeted attacks, utilising creative strategies and human insight to uncover hidden vulnerabilities. Ethical hackers adopt the mindset and methods of cybercriminals, including sophisticated techniques such as social engineering and custom exploit development.

A professional penetration tester will be able to replicate what a hacker would do if they were trying to gain unauthorised access into your security system. The penetration tester will get a clear picture of the architecture of your system and attempt to infiltrate it, just like a hacker would.

The purpose of this is to locate where exploitable information can easily be retrieved, but also to give you a full and detailed report on the security of your system, where the biggest weak points are and where your system may be secure. Achieving this level of penetration test is incredibly technical, and many penetration testers develop their own tools to be able to really analyse varying systems.

A penetration test provides a clear and controlled understanding of what the business impact would be if a hacker used an open vulnerability to stage an attack.

The Importance of Human Expertise in Penetration Testing

Automation alone can’t replicate the creativity and intuition humans with security expertise can bring to penetration testing. Penetration testers “chain” vulnerabilities by identifying and exploiting multiple weaknesses in a system, often starting with a seemingly minor vulnerability to gain access and then escalating privileges to achieve a larger impact, simulating real world attack scenarios.

Human testers effectively exploit the chained vulnerabilities, creating custom exploits to uncover complex weaknesses, just like a real-life hacker would – and that automated scanners would miss.

Real world scenarios underscore the critical role human analysis plays in identifying sophisticated threats.

When Businesses Should Conduct Pen Testing

Pen testing should be conducted annually at a minimum, or after any significant system changes, for regulatory compliance purposes, or in response to specific security incidents or strategic events like mergers and acquisitions.

Limitations of Pen Testing Compared to Vulnerability Scanning

Pen tests are extremely thorough; however, they are resource intensive, requiring considerable time, human expertise, and allocated spend.

The detailed nature of pen tests make them less suitable for frequent, broad assessments, which vulnerability scans are much more suited to.

Key Differences Between Pen Testing and Vulnerability Scanning

Pen Testing vs. Vulnerability Scanning

Automated scanning excels in speed, scalability, and efficiency, suitable for regular security checks. However, manual pen testing offers deeper insights and accuracy, essential for identifying sophisticated or logic-based vulnerabilities.

Key Differences:

• Automation vs. Manual Effort: Vulnerability scanning is automated, while penetration testing involves significant manual testing
• Breadth vs. Depth: Vulnerability scanning covers a wide range of potential issues, whereas penetration testing goes deeper into how those issues could be exploited
• Output: Scans provide a list of vulnerabilities, whereas pen tests provide actionable insights and proof of exploitation
• Frequency: Scans are frequent, often conducted on a monthly basis, while penetration tests are typically conducted annually or after major system changes
• Purpose: Scanning ensures systems stay patched and up to date against known vulnerabilities, pen testing evaluates the real world effectiveness of your security measures against malicious actors

Compliance & Regulatory Considerations

Compliance frameworks like ISO 27001, PCI DSS, DORA, and NIS2 mandate security assessments. While vulnerability scanning helps achieve baseline compliance, pen testing meets more rigorous regulatory demands, validating real world security resilience.

Cost comparison: Penetration Testing vs. Vulnerability Scanning

Vulnerability scanning is budget friendly, scalable, and ideal for routine assessments.

Penetration testing, although more costly, delivers comprehensive insights crucial for addressing strategic vulnerabilities and regulatory compliance.

Example: How a Vulnerability Can Escalate Quickly and Become a Danger To Your Business

An IT manager is aware of an open vulnerability on a backend database system, and has been meaning to get it mitigated through patching or software upgrade. However, due to time constraints, or not gaining business approval for the system to be unavailable during patching, this has not been completed. They are not that concerned as the vulnerability has no direct internet access and is separated on its own network segment.

During a penetration test an ethical hacker was able to gain access to the internal network due to a vulnerability on the perimeter firewall that was unknown to the IT department. The ethical hacker was able to bypass network separation, as it was misconfigured, allowing them to gain access to the backend database without having to go through any perimeter security device such as a firewall.

Due to the open vulnerability the ethical hacker was able to dump the data that was stored on the database. Unfortunately, the data was sensitive in nature and could damage the reputation of the organisation, and be subject to heavy regularity fines. Now armed with this information that would never be highlighted during a vulnerability scan the IT manager is able to articulate the business risk and its impact to senior management, and has the full backing of the board and the required budget to have this vulnerability fixed.

When to Use Pen Testing vs When to Use Vulnerability Scanning

Both penetration testing and vulnerability scanning play essential roles in cybersecurity.

When you break the two processes down, they are incredibly different. Yet many businesses fall into the trap of paying for a ‘cheap’ penetration test that is actually a vulnerability test in disguise.

When it comes down to which is best for your business, both are essential to maintain comprehensive security, which is why it is essential to make sure that the penetration test that you’re paying for, is actually a penetration test, not an off the shelf vulnerability scan.

Optimal security strategies integrate both methods to balance effectiveness and cost and provide year round security insights.

Best Practices for Security Testing Based on Business Needs

Develop a structured security assessment strategy combining frequent automated scans with periodic manual pen tests. These should be conducted annually as a minimum. Tailor your approach based on your risk exposure, regulatory requirements, and budget.

Industry-Specific Considerations

Industries such as finance, healthcare, government, and critical national infrastructure have specific mandates from the likes of DORA and NIS2, and heightened risk profiles, requiring detailed manual penetration testing complemented by routine automated scanning.

Why a Combined Approach is Often the Best Solution

Integrating automated scanning with manual pen testing offers comprehensive coverage. Automated scans quickly identify common vulnerabilities, while manual testing provides deeper analysis to uncover sophisticated attack paths.

How DigitalXRAID Helps Businesses with Security Testing

DigitalXRAID specialises in customised cybersecurity assessments, combining advanced, CREST approved tools, with expert human analysis, to provide unmatched protection.

DigitalXRAID’s Approach to Penetration Testing

Our penetration testing services use industry leading methodologies, such as OSINT, combining manual and automated techniques to simulate realistic attacks. Accredited by both CREST and CHECK (NCSC), we provide actionable insights tailored specifically to your business.

DigitalXRAID’s Vulnerability Management Services

Our vulnerability management services provide continuous scanning complemented by human oversight. This unique approach significantly reduces false positives from automated scans and ensures critical vulnerabilities are promptly addressed following expert guidance.

Case Study: How DigitalXRAID Helped Breast Cancer Now Strengthen Security

DigitalXRAID delivered a hybrid security assessment for Breast Cancer Now, combining automated vulnerability scans and manual pen tests to ensure that infrastructure and web applications are secure.

By engaging DigitalXRAID as a trusted security testing service provider, Breast Cancer Now has taken steps to ensure its internal and external infrastructure is safeguarded effectively, with regular penetration testing and vulnerability scanning. Even with updates to infrastructure, regular testing ensures that Breast Cancer Now remains secure.

DigitalXRAID was able to identify vulnerabilities overlooked by automated scanning alone, providing actionable remediation strategies that significantly enhanced their security posture and regulatory compliance.

Regular manual pen testing and regular vulnerability scanning compliments other cybersecurity measures that Breast Cancer Now has taken, including achieving Cyber Essentials Certification. Pen Testing is able to uncover a far deeper level of issues than vulnerability scanning alone can achieve, so this has successfully increased the maturity of Breast Cancer Now’s security posture.

Making the Right Cyber Security Decision for Your Business

Key Takeaways on Pen Testing vs Vulnerability Scanning

• Vulnerability Scanning: Quick, cost effective, frequent assessments. Ideal for routine monitoring.
• Penetration Testing: Deep, comprehensive assessments essential for strategic insights, regulatory compliance, and identifying sophisticated threats.
• Combined Approach: Provides optimal balance and constant insights, maximising security effectiveness and cost efficiency.

Next Steps: Book a Security Consultation with DigitalXRAID

Don’t leave your cybersecurity to chance. Contact DigitalXRAID today for a tailored consultation, and secure your business with a cyber security strategy built precisely around your needs. Get in touch today.