Penetration Tests vs. Vulnerability Scans: What’s the Difference?

What is a vulnerability scan?

A vulnerability scan identifies and reports points of weakness in your firewalls, software and web applications, servers, and other devices connected to your corporate IT systems. Vulnerability scanning is an integral part of a company’s vulnerability management process and overall security posture.

There are two types of vulnerability scans: internal and external.

An internal scan aims to find vulnerabilities in your company’s internal networks (that is, endpoints) whereas external scans are performed on your company’s external systems (the network perimeter). Simply put, an external scan checks the locks on your house’s entrance doors and windows; an internal scan checks the locks on the doors of individual rooms in the house.

To perform the assessment, companies use a vulnerability scanner, which is an automated security scanning tool that finds known vulnerabilities. Remember, this means a vulnerability assessment will not find zero-day vulnerabilities (that is, vulnerabilities that are not yet known to the vendor that manufactures the software or hardware in question).

How often should I do a vulnerability scan?

Security professionals recommend performing a vulnerability scan more often than a penetration test: at least once per quarter, compared to a yearly pen test.

The cadence of the scans also depends on the cybersecurity regulations or frameworks that your company must comply with. For example, the PCI DSS framework requires that companies perform quarterly vulnerability assessments. In contrast, the HIPAA Security Rule doesn’t require a vulnerability scan — but it does require that all business associates conduct a risk analysis, which is meant to find any potential risks and vulnerabilities to the ePHI that they store, handle, or transmit.

What is a penetration test?

A penetration test is conducted by a team of penetration testers, or ethical hackers, and is used to identify and test entry points within an organization’s security environment to expose potential vulnerabilities and exploit weaknesses.

“Pen testing” is often carried out as a simulated cyber attack to determine how easy it will be for cybercriminals in the real-world to exploit potential vulnerabilities and hack into the organization’s internal networks. Therefore, pen testing generally provides a more effective way to expose and manage an organization’s overall cybersecurity risk, compared to a vulnerability assessment.

How often should I do a penetration test?

The nature of cybercrime is always evolving; today’s cybercriminals are far more advanced and sophisticated in the tactics, techniques, and procedures (TTPs) they leverage to launch cyber attacks than those that existed in the past year.

So it’s highly recommended that organizations should do a pen test at least annually, although more security-focused organizations will opt for twice a year. Since attackers’ TTPs change every year, it’s up to your organization to ensure it stays ahead of the threat curve and finds weaknesses in your security posture that can be targeted.

In addition, you also have to consider whether your business must adhere to any regulations or industry frameworks that dictate how often you need to conduct a pen test. For example, the PCI DSS requires that a pen test must be conducted at least once a year to maintain compliance.

Vulnerability scanning vs. penetration testing: Key differences

Although pen tests and vulnerability scans sound similar in scope, there are some key differences.

Automation vs. manual testing

• Vulnerability scan: relies entirely on security scanning tools so it’s completely automated in its assessment. The scan casts a wide net over the entire network.
• Pen testing: involves a combination of automated tools and manual testing from experienced penetration testers to find the exploits.

Exploiting any found vulnerabilities

• Vulnerability scan: only aims to discover vulnerabilities, not to exploit them.
• Pen testing: any found vulnerabilities are exploited to assess the strength of the security posture. Since pen testing also relies on using creative tactics and techniques to hack the internal networks, it’s likely that the penetration testers may discover a zero-day vulnerability in the process.

Detective vs. preventive controls

• Vulnerability scan: a detective control, which means the priority (and the goal) is to detect problems.
• Pen testing: a preventive control, which means the priority is to identify vulnerabilities and use the findings to prevent those weaknesses from being exploited in the future.

Financial investment required

• Vulnerability scan: low-to-moderate cost, since it usually on involves the use of tools.
• Pen testing: high cost, since organizations usually engage an external pen testing team to perform the pen test and penetration test report findings.

Questions to ask when deciding between a penetration test and vulnerability scan

Both a vulnerability scan and a pen test are critical to strengthening an organization’s overall security posture, and each serves a specific purpose.

So what are some questions you should ask yourself when deciding on which service your organization needs?

Consider the following:

1. Do you have to conduct a specific test as part of a regulatory compliance requirement?
2. What is the result that you’re trying to achieve? Do you only want to report on existing vulnerabilities to your senior management, or do you want to take a more active, targeted approach to prevent cyber attacks?
3. What does your security budget look like? Can you engage a team of external penetration testers to dig deep into your security infrastructure and find holes?
4. Are you trying to take a proactive approach or a reactive approach? While a vulnerability scan can help with either scenario, a pen test is best used as a proactive approach to build stronger security defenses.
5. Have cybercriminals exploited a new vulnerability or has a vendor released information for a zero-day exploit? If so, a vulnerability scan is likely the best approach; it’s cost-effective and will help your team identify whether that vulnerability exists in your network.
6. Has your team onboarded a new technology, application, or changed your IT infrastructure recently? If so, there may be a high risk of misconfigurations, which can be easily exploited by cybercriminals, so conducting a vulnerability scan on each occasion is a great way to assure all systems are protected.
7. How confident are you about the strength of your security posture and your ability to defend against the toughest cyber threats? A pen test is your best bet to test your defenses, validate the ongoing remediation efforts, and fix any noticeable weaknesses.

Secure Your Data With ZenGRC

Reciprocity’s ZenGRC is risk management software that helps organizations manage vulnerability assessments and penetration tests as part of the greater security assessment plan.

In addition, ZenGRC provides continuous risk monitoring and reporting so organizations can spend less time on menial follow-up tasks to manage cyber risk and focus more on strengthening their security posture.

Schedule a demo today to learn how ZenGRC can help your organization improve vulnerability assessments and penetration testing.