Attackers do not need to be clever to break into most small businesses. They run automated tools that look for known flaws: an unpatched VPN, an old Windows server, a forgotten remote access port. If those tools can find your weak spots, you should find them first.
That is what a vulnerability scan does. It is one of the cheapest, most repeatable security habits a small business can build, and cyber insurers and compliance frameworks increasingly expect it. Here is how to do it without a security team.
What a vulnerability scan is (and is not)
A vulnerability scanner checks your devices and network equipment against a database of publicly known flaws. It reports missing updates, outdated software, default passwords, weak encryption settings, and unnecessary open ports, each with a severity rating.
It is not a penetration test, where a person tries to exploit weaknesses to show real impact. It is also narrower than a cybersecurity risk assessment, which weighs people and process too. Think of the scan as the smoke detector: fast, automated, and best run often.
1. Decide what to scan
Start with two views of your business, because attackers see only one of them:
- External scan: everything reachable from the internet, such as your firewall, VPN, website, mail server, and any exposed remote desktop. Findings here are the most urgent.
- Internal scan: laptops, servers, printers, and cameras on your office network. These findings matter most once an attacker or ransomware is already inside.
Do not forget cloud accounts. Misconfigurations in Microsoft 365 or Google Workspace are vulnerabilities too, and our guides to Microsoft 365 settings and cloud misconfiguration cover them. An up-to-date asset list keeps the scope honest, because a scanner cannot check a device you forgot you owned.
2. Run the scan and triage the results
Options range from free tools such as OpenVAS, to built-in cloud security scoring, to commercial scanners bundled with managed IT services. The tool matters less than the routine. Run authenticated scans where possible, since logging in to the device finds far more missing patches than looking from outside.
A first scan often returns hundreds of findings. Do not panic, and do not try to fix everything. Triage in this order:
- Internet-facing and critical: fix within days. Anything listed as actively exploited goes here.
- Internal and critical or high: fix within a couple of weeks.
- Medium and low: batch into regular maintenance.
Watch for false positives, and for findings on end-of-life systems that cannot be patched. For those, the real fix is replacing the device or isolating it with network segmentation. Our posts on the Windows 10 end of support and actively exploited VPN flaws show why those two categories deserve attention first.
3. Fix, rescan, and keep the evidence
Most findings come down to a short list of fixes: apply updates, remove software nobody uses, close ports you do not need, change default passwords, and turn on multi-factor authentication. A working patch management routine clears the bulk of findings automatically.
After fixing, rescan. A finding is not closed until a scan says so. Save each report with its date, and track open items with an owner and a due date. That record answers cyber insurance renewal questions and customer security questionnaires, and for card payments it supports PCI compliance, which requires regular scanning.
Common mistakes to avoid
- Scanning once and never again. New flaws are published daily, so a clean report is only good for a few weeks.
- Treating the report as the goal. The value is in the fixes, not the PDF.
- Scanning only the office network and ignoring what the internet can see.
- Scanning systems you do not own or have permission to test. Always get written authorization first.
The takeaway
A vulnerability scan will not make you secure on its own, but it removes the easy wins attackers rely on. Scope what matters, scan monthly, fix the internet-facing and critical findings first, and rescan to prove it. Pair it with a yearly risk assessment and you will be ahead of most businesses your size.
Frequently asked questions
What is a vulnerability scan?
A vulnerability scan is an automated check that compares your devices, servers, and network equipment against a database of known flaws, such as missing security patches, outdated software, weak settings, and open ports. It produces a ranked list of issues to fix.
How often should a small business run a vulnerability scan?
Monthly is a good target for internal and external scans, and also after any major change such as a new firewall, server, or cloud app. Some insurance and compliance frameworks such as PCI DSS require scans at least quarterly.
What is the difference between a vulnerability scan and a penetration test?
A scan is automated and finds known weaknesses. A penetration test is performed by a person who tries to exploit weaknesses to show real impact. Scans are cheap and frequent; penetration tests are deeper and usually done once a year or less.
Are free vulnerability scanners good enough?
Free and built-in tools are a reasonable start for a small network, especially for external exposure and missing patches. Their weak point is not detection but follow-through: results only help if someone reviews them and fixes the findings on a schedule.
Is it safe to run a vulnerability scan on my own network?
Yes, when it is scoped and scheduled. Scan only systems you own or are authorized to test, avoid business hours for older equipment such as printers and legacy servers, and tell your IT provider first so nobody mistakes the scan for an attack.
Want a vulnerability scan you can actually act on?
Ghosxt scans your network and cloud accounts, turns the findings into a prioritized fix list, and handles the fixes. You talk directly to the owner. See current pricing or our cybersecurity services.
Book your free assessmentPrefer to talk first? Email sales@ghosxt.com or call (831) 204-0501.