Vulnerability Scans or Pen Tests: Which Are More Critical for Your Cyber Plan?

The best cybersecurity programs have layered approaches to security, and they monitor the resilience and effectiveness of those layers constantly.

Security professionals have a variety of tools for this at their disposal, and an excellent cyber plan includes both vulnerability scans and penetration testing to get after security vulnerabilities through multiple avenues. 

However, if a business has the budget for only one of these services, which is the most critical? Which tool, if neglected, could have a worse impact on the network? Let’s find out. 

What’s the Difference Between Vulnerability Scans and Pen Testing?

Before determining which is more important, it’s helpful to review the difference between these two different cyber tools. 

Vulnerability scans are automated scans that are designed to help identify potential vulnerabilities in network devices. These devices might include switches, routers, firewalls, applications, or servers. 

Vulnerability Scans

Vulnerability scans are usually carried out by an organization’s IT department, or the service provider they utilize for IT support if they don’t have a dedicated team. 

As mentioned above, these scans are usually automated and can be set to be done automatically at certain intervals. Based on the industry, there are certain regulatory standards that must be adhered to as to how often vulnerability scans need to be done, and what they need to scan. 

Scans can be done either internally to the network, or externally. In either case, scans check for known vulnerabilities on a network that could be exploited. 

These could include a multitude of vulnerabilities, but some of the most common include:

• Weak or outdated encryption
• Self-signed certificates
• Outdated operating systems
• Issues with permissions

One important thing to note is that scans can only look for known vulnerabilities; in other words, they’re not effective against zero-day exploits. Nevertheless, vulnerability scans are a critical part of any network defense strategy. 

Pen Testing

Vulnerability scanning doesn’t actually do anything, however; it just reports on potential issues with cybersecurity. In other words, it’s non-intrusive. 

It’s most effective when used in conjunction with periodic penetration testing, or pen testing. Pen testing is when a professional performs active tests on vulnerabilities on your system, to see if they could gain unauthorized access to any portions of your network. 

Pen testing is best done as a portion of a holistic cybersecurity plan, and it can help validate some of the vulnerabilities a simple scan discovers. 

Vulnerability scans are known for returning a fair amount of false positives, but a good pen tester can attempt to exploit those results to see if there are other controls already in place that mitigate the vulnerability. They can also determine if it’s even a true vulnerability. 

Since pen testing requires a professional to carry out, it’s usually more expensive than vulnerability scans. However, a company could consider bringing in a pen tester for limited testing if a scan returns a particularly critical vulnerability. 

Focusing on the scope of pen testing is a way to decrease both the intrusiveness of the test, as well as the cost to perform it. 

Pen testing is a critical part of network security because it replicates a real-world scenario where a hacker might try to gain access to a network. A good pen tester can replicate those conditions and find holes or security gaps that vulnerability scans simply can’t identify. 

So Which One’s More Important for Your Network?

Now that we have a basic understanding of the difference between vulnerability scans and pen testing, which one of these tools is actually more critical for your cyber plan? 

At first, one might think vulnerability scans are more important. Indeed, running regular scans should be built into a cyber plan. These scans, in addition to running at set intervals, should also be conducted whenever there is a major network change. 

This allows the IT team and cyber team to ensure that any new changes or network topology aren’t introducing unforeseen vulnerabilities to the rest of the network. Some vendors even sell scanners that identify and scan any new devices added to a network, which can help teams identify potential issues prior to a regularly scheduled scan.

However, in order for a cyber plan to be truly effective, enterprises can’t skip periodic pen testing. Sure, malicious actors will run external vulnerability scans to identify gaps the same way the company will be, but those actors can exploit vulnerabilities in ways that scans simply can’t predict. 

Pen testers are the pros you call when you have vulnerabilities but need to make sure they’re actually gaps to be concerned about. They can give you an outside perspective and ensure you know whether your network is truly secure. They provide a service that most replicates the situation a bad actor will experience. 

Even if you conduct pen testing less frequently than vulnerability scans, or only after a major vulnerability is identified, it’s important to build regular pen testing into your cyber plan. Doing so can help give you the peace of mind that your network is secure, and that you’re aware of the gaps and are taking steps to close them. 

For those reasons, and for the extra layer of security that pen testing provides, they’re the more critical tool for your cyber plan to be truly successful.