TechKnowSurge
TechKnowSurge Catalog Videos Common Network Vulnerabilities
VideoSecurityFree

Common Network Vulnerabilities

Common network vulnerabilities include insecure wireless and wired connections, open service ports, and misconfigurations that expose systems to unauthorized access. Keeping firewall rules and network settings current is essential to reducing attack surface across an organization's infrastructure.

⚑ Complete this video to capture a CTF flag worth 1 point.

About this video

Networks present a broad attack surface that spans wireless signals, wired infrastructure, and Bluetooth connections on individual devices. Wireless communication is inherently exposed because signals travel through open air and can be intercepted by anyone within range. Encryption reduces this risk but does not eliminate it entirely, leaving wireless traffic vulnerable to passive interception by determined adversaries. Understanding these built-in technological limitations is a foundational step in building a more secure network environment. Open service ports represent another significant source of risk. When applications communicate with servers across specific ports, those ports must be open on both the endpoint and the firewall. Each opening in a firewall—particularly on the network perimeter—creates a potential pathway for attackers to reach internal resources. The more ports exposed to outside traffic, the greater the overall vulnerability, making careful port management a critical administrative responsibility. Misconfiguration is one of the most frequently observed causes of network vulnerability in real-world environments. A single improperly configured firewall rule can expose an entire network, and settings that made sense at one point in time may become liabilities if they are never revisited. A common example involves firewall rules created to allow traffic to a web server that is later decommissioned. If those rules remain in place after the server is removed, any new device that inherits the same IP address becomes unintentionally reachable from outside the network. Maintaining accurate, up-to-date network configurations is essential to preventing this class of vulnerability.

What you'll learn

What's covered

Common Network Vulnerabilities

Key terms

Vulnerability
A weakness in a system, application, or process that can be exploited by a threat actor.
Firewall
A network security device that monitors and controls incoming and outgoing traffic based on predefined security rules.
Port
A logical endpoint for communication in a network, identified by a number that specifies a particular service or application.
Wireless Access Point
WAP
A device that allows wireless devices to connect to a wired network using Wi-Fi.
Encryption
The process of converting readable data into an unreadable format using an algorithm and key to prevent unauthorized access.
Misconfiguration
An incorrect or insecure system or service setting made by an administrator that can expose vulnerabilities affecting confidentiality, integrity, or availability.
Patch Management
The process of acquiring, testing, and installing software updates to fix vulnerabilities and improve functionality.
Attack Surface
The total set of points in a system where an unauthorized user can attempt to enter or extract data.

Topics

Network Security Firewall Configuration Wireless Security Open Ports Network Vulnerabilities Attack Surface

Transcript

Insecure Networks

Quite often we find our networks are insecure. It could be the wireless network, it could be the wired network, it could be Bluetooth on the individual devices. So there are different aspects to the network that we need to make sure are secure.

Some of this is just inherent technology vulnerabilities. As an example, wireless: it all gets sent out through the air, and anybody within a certain range could pick that up. This is problematic because that communication is just out in the open. There are ways that we can secure this, but even if we secure it and make it encrypted, there's still an element of it that is exposed to anybody who wants to listen in on that, anybody who wants to eavesdrop on that.

Open Service Ports

When devices are talking — let's say this machine right here has some sort of app on it and it's talking to a server, and this server has some sort of service that's running on it — well, they're communicating back and forth, and they're communicating across a port. These open service ports can cause problems across the network.

The open service ports could be on the individual machines, or it could be in the firewall. Maybe you have a hole in the firewall for a specific port so you can come back. Maybe it's some sort of web server here, so you want people to be able to access that web server. Making it free flowing is a good thing in many ways, because then it allows a bunch of different communication and less administration to it, but it also could cause problems, because these open service ports can be issues, especially on our outside firewall. If we're poking a bunch of holes in the firewall for all these different ports to inside resources, each one of those opens us up for more problems, for more vulnerabilities.

Misconfiguration

Misconfiguration could be another big issue on our network. In fact, I've seen this probably more so than anything else, that something gets misconfigured and opens up a vulnerability. So if we were to misconfigure this firewall, that could expose our whole network. If we misconfigure our communication across this network, then that could be very problematic and open us up for a lot of risk.

Outdated Settings

There also could be outdated settings, if we don't go back and configure things differently later on. That could be problematic as well.

Let's say we have a web server up and running within our network, and we put a hole in our firewall so that way people can get to that port 80 and port 443 on our web server so they can get web services. Well, what happens when we take down the server? Maybe we remove this server and we set up a whole other machine. Maybe it's somebody's laptop, maybe it's a desktop, maybe something else that takes its place from an IP perspective, but we never change the firewall. If that hole is still poked into the inside, then it can get to that new machine on that port 80 or port 443. So it could be problematic if we don't keep our settings updated.

About TechKnowSurge

TechKnowSurge builds IT and cybersecurity professionals through hands-on, concept-first training built around real understanding — not memorization. Free interactive tools, structured programs, and 25+ years of real-world experience, all in one place.

Explore free tools and programs →