Port Scanner

Find open and exposed ports on your server before an attacker does.

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Every open port is a door into your server. Most are meant to be there — but the dangerous ones are the services you forgot were running: an old database listening on a public IP, a debug port left open after a deploy, an admin panel exposed to the whole internet. A port scanner shows you exactly what the outside world can reach, so you can close what should never have been open.

What it checks
  • Open TCP ports across the common and well-known ranges
  • The service and version likely running behind each port
  • High-risk ports exposed to the public internet (databases, RDP, admin panels)
  • Unexpected changes — a port that opens after a deploy or config change
  • Whether ports that should be firewalled are actually closed

Why it matters

Attackers scan the entire internet for exposed services around the clock. An open database or remote-access port is often all it takes. Because your server changes over time — new software, deploys, config tweaks — a port that was safely closed last month can quietly reopen. Continuous scanning catches that drift before someone else does.

How BrandSentryPro does it

Add your server as a monitor and BrandSentryPro scans its ports on a schedule, grades what it finds by risk, and alerts you the moment a new or dangerous port appears. No manual `nmap` runs, no remembering to check — it watches for you.

Frequently asked questions

What is a port scanner?
A port scanner connects to a range of network ports on a server to see which ones are open and accepting connections. It tells you which services are reachable from outside, so you can spot exposure you did not intend.
Which open ports are dangerous?
Ports exposing databases (3306, 5432, 27017), remote access (22, 3389), and admin or debug interfaces are the highest risk when reachable from the public internet. Public-facing web ports (80, 443) are normal; the danger is anything internal that leaks out.
How often should I scan for open ports?
Continuously. Ports change as you deploy and reconfigure, so a one-time scan goes stale fast. BrandSentryPro re-scans on a schedule and alerts you when something new opens.

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Add a monitor and BrandSentryPro keeps every check running for you — with alerts the moment something needs attention.

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