Vulnerability scanning: what it finds and how often to run it

Understanding vulnerability scanning and its role in your defense

If you want to keep your business safe, you need to know where your weaknesses are. Vulnerability scanning is the process of using automated tools to inspect your network, computers, and applications for known security flaws. Think of it like a home inspector checking your house for cracks in the foundation or outdated wiring. The scanner looks for things that a hacker might use to break into your system, such as a piece of software that hasn't been updated or a setting that was accidentally left open. By doing this regularly, you can fix these problems before they become a real threat.

For a small business, vulnerability scanning is one of the most cost-effective ways to reduce risk. Most cyber attacks do not use sophisticated new techniques. Instead, they target known holes in common software like Windows, Adobe, or WordPress. These holes are public knowledge, and hackers use automated programs to search the internet for any company that hasn't patched them yet. A vulnerability scan lets you see your business through the eyes of a hacker, giving you a chance to close the door before they arrive.

What a vulnerability scan actually finds

A typical scan looks for thousands of different issues across your entire environment. It checks your 'attack surface'—which is every point where a hacker might try to touch your systems. This includes your office Wi-Fi, your website, your employee laptops, and your cloud servers. The scanner compares what it finds against a massive database of known vulnerabilities, often called CVEs (Common Vulnerabilities and Exposures).

• Missing Patches: Outdated software that has known security bugs.
• Default Passwords: Devices or services that are still using 'admin' or other factory settings.
• Weak Encryption: Older ways of protecting data that are now easy for hackers to crack.
• Open Ports: Unnecessary pathways into your network that should be closed.
• Misconfigurations: Security settings that were set up incorrectly and leave you exposed.

Internal vs. External vulnerability scanning

There are two main types of scans you should know about. An 'external' scan looks at your business from the outside, just like a hacker on the internet would. it checks your website, your email servers, and your office firewall. An 'internal' scan is performed from inside your network. It looks at the devices your employees use every day. Both are important. External scans catch the most obvious entry points, while internal scans help you stop a hacker from moving around if they manage to get past your front door. For a complete picture, you should run both types of scans on a regular basis.

How often should you run a scan?

The frequency of your scanning depends on your business and the regulations you follow. At a minimum, most security experts recommend running an external scan once a month. However, if you handle a lot of sensitive data or have a large number of employees, weekly scans are better. You should also run a scan whenever you make a major change to your technology, such as installing a new server or moving to a new office. The world of cyber threats moves fast—thousands of new vulnerabilities are discovered every month—so a scan that was done six months ago is no longer useful.

For businesses that accept credit cards, the PCI DSS standard requires quarterly scans performed by an 'Approved Scanning Vendor.' Similarly, many cyber insurance companies now ask for proof of regular scanning as part of their renewal process. If you can show that you are actively looking for and fixing vulnerabilities, you are seen as a much lower risk.

Moving from scanning to management

Finding a vulnerability is only half the battle. The most important part is fixing it. This is why we often talk about 'Vulnerability Management' rather than just scanning. Management involves a cycle of scanning, prioritizing the results, fixing the issues (patching), and then scanning again to make sure the fix worked. For a small business, this can feel overwhelming. Many choose to work with a partner who can handle the technical work of patching so the business owners can focus on their actual work.

1. Create an inventory of all your internet-connected devices and software.
2. Schedule your first external vulnerability scan to identify the most obvious risks.
3. Review the report and focus on fixing 'Critical' and 'High' severity issues first.
4. Apply software updates and security patches to your most important systems.
5. Set up a recurring monthly scan to ensure new threats are caught quickly.

Common pitfalls to avoid

One common mistake is running a scan but never looking at the report. A scan is just a list of homework; if you don't do the work, you aren't any safer. Another mistake is scanning only your office computers and forgetting about your remote workers. Hackers will often target the weakest link, which might be a laptop at someone's home. Finally, don't assume that a clean scan today means you are safe forever. New vulnerabilities are found every day, which is why consistency is the key to a good defense.

• Do you have a current list of all devices connected to your network?
• Have you run an external scan of your website and firewall in the last 30 days?
• Do you have a process for applying software patches when they are released?
• Does your industry require specific scanning for compliance (like HIPAA or PCI)?
• Do you scan the laptops of your remote employees as well as your office staff?