Common Types of Network Vulnerabilities and Threats

Various types of network vulnerabilities can pose significant challenges for companies and organizations of all sizes, as they can lead to exposed sensitive data and disrupted critical operations. And with cybercrime on the rise, network vulnerabilities have never been more important to understand. By understanding the different types of network security vulnerabilities and how they can be exploited, you can take steps to shore up your defenses and protect your organization.

In this blog post, we'll be discussing the most common types of network vulnerabilities along with examples. By the end, you'll be armed with all the information you need to protect your business from cybercrime.

What is Network Security Vulnerability?

A network vulnerability is a weakness in the network's computer systems that can be exploited by attackers. These network security vulnerabilities can exist in the network infrastructure, the operating system, the applications or the users themselves.

Attackers can use the network vulnerabilities to gain access to systems and data, or to disrupt network service.

Let's find out the most common network security threats and their types in the next sections.

Watch our video for a quick summary:

Common Network Threats

While there are many types of vulnerabilities in network security, some are more common than others. In this section, we'll go over some of the most common threats to your network security.

But first, it's valuable to emphasize at this point that the importance of network security cannot be overstated. Many organizations view their network as an impenetrable fortress far away from security breaches, but the truth is that it can be surprisingly easy to hack into a network when the attacker knows where to look, and many indeed know.

Network vulnerabilities in general can run into hundreds. But there are a couple that are quite common, yet also happen to be the most overlooked or underrated.

Here we share the top 5 most common network vulnerabilities that all organizations plus their teams really need to be wary of.

1. Ransomware

Ransomware is a type of malware that encrypts data on a victim's computer and holds it hostage until a ransom is paid.

The victim is given a countdown timer and often threatened with severe security consequences such as data deletion if the ransom isn't paid on time. Ransomware is particularly insidious because it can take over an entire network, encrypting files on every computer on the network.

Ransomware is one of the most scary of the common network threats and costs businesses worldwide millions in damages. It’s also embarrassing.

To protect your business from ransomware, make sure to install anti-virus software and keep it up to date, back up your data regularly, and restrict access to sensitive data to only authorized users.

2. DDoS

DDoS stands for Distributed Denial-of-Service (DDoS). A DDoS attack is when a hacker sends overwhelming amounts of traffic to a website or server, so much that it can no longer handle legitimate requests.

The malicious attacker literally floods a network with so much traffic that it can't function. This can be done in a number of ways, but one common method is to send a huge number of packets to the target server. The server can't keep up with the demand and eventually crashes under the load.

The first ever known DDoS attack surfaced in 1996. The victim was Panix, an ISP that is considered the oldest provider in New York. Panix was taken offline for many days by DDoS weapon SYN food. SYN food is known to exploit vulnerabilities in a server’s TCP three-way handshake, rendering the server unresponsive.

Vulnerabilities that allow DDoS attacks can take a website offline or make it so slow that users can't access it. There are several ways of preventing network vulnerabilities that invite DDoS attacks, including using a third-party service and increasing your bandwidth.

3. IoT vulnerabilities

The use of IoT devices is increasingly becoming commonplace, and herein lies a major threat to networks as criminals look out to take advantage of vulnerabilities in IoT installations.

Hackers can insert malicious code into an incredibly large number of vulnerable IoT devices, directing them to stream packets and ambush an organization's network with damaging attacks.

One of the most memorable attacks that exploited IoT vulnerabilities is the Mirai botnet attack that occurred in 2016 and left a trail of IoT driven damage. We'll get into this in detail under types of vulnerabilities in the next section.

4. Phishing

Phishing is one of the most common network attacks and sits atop among the most notorious vulnerabilities that you must watch out for. Attackers exploit the system by using fraudulent emails or websites to steal personal information from users.

A report by IBM indicates that phishing is the top vulnerability exploited by attackers, hitting even top global brands like Apple, Google and Microsoft. The report found that 50% of targeted victims actually clicked on phishing campaigns, exposing their organizations to costly threats.

Attackers can exploit phishing vulnerabilities to steal your teams' login IDs (usernames) as well as passwords. A good example of a phishing attack is when a user opens what appears to be legitimate email. But hidden inside the deceiving email is a malware code that logs out the user as soon as they open it. Once the user logs back after being logged out, the malware captures their keystrokes. These keystrokes are all the criminals need to get the usernames and passwords.

5. SQL injection

Another most common network threat is SQL injection. Attackers use SQL injection to exploit vulnerabilities in a database, allowing them to access and manipulate data.

In this attack, the hacker sends specially crafted SQL statements to the target database in an attempt to extract data or execute commands. They may even be able to gain control of the entire database server. They can steal information such as passwords and credit card numbers, or even take over full control of the database.

Impact of SQL injection

SQL injection can have the following impacts:

• Attackers can enter the database servers with OS permissions and gain access to sensitive systems within the network.
• Attackers can compromise or introduce dangerous foreign data to the database
• Attackers can get hold of credentials, impersonate legitimate users and use their privileges to inflict damage to the network.
• Attackers can delete records in the database or even get rid of entire tables.

There are a number of ways to protect your database from vulnerabilities that criminals can exploit to introduce SQL injection attacks. One is to use parameterized queries, which are queries that are prepared ahead of time and don't allow for user input.

You can also use stored procedures, which are routines that can be executed from within the database itself. These procedures help to protect against SQL injection attacks by limiting the types of data that can be accessed and processed.

Types of vulnerabilities in network security

Network security vulnerabilities and threats come in many different shapes and sizes, but can generally be divided into three main categories: hardware network vulnerabilities, software network vulnerabilities, and human error vulnerabilities.

They all have the potential to cause serious damage to your business. One of the best ways to safeguard your network against the most complicated vulnerabilities is to use professional network support services.

All manner of vulnerabilities are likely to fall into the following 3 most common types of threats in network security:

1. Hardware vulnerabilities

Hardware vulnerabilities are flaws in the physical system that attackers can exploit. The attacks can be executed remotely or by physically accessing the hardware system.

Any loophole that can permit malicious code into the physical network and destroy devices inherently falls under network security threats and vulnerabilities of the hardware type.

These flaws can exist in the design or in the manufacturing process. Attackers can exploit hardware vulnerabilities that allow full system control to gain access to sensitive data or to take control of the system.

Hardware network vulnerabilities are a major concern for companies and organizations that rely on computer systems for critical operations. Here are the common categories of hardware vulnerabilities:

Unauthorized access to physical devices

Unauthorized access to physical devices in the network is the easiest way to compromise a network. The intruder will quickly install malware, which can then be used to spy or breach data. The malware can now monitor your internal events including traffic.

It's worth noting that the physical access here does not have to be in person. The criminals can mail malicious devices such as USB drives or phones as “gifts”' to an employee within the company. The receivers, without knowledge, will use these devices within the network and end up installing the malware themselves.

Other devices like mobile phones and laptops can be stolen then be used to access the network from outside, via VPN. So it's critical to ensure that all devices have strong passwords in addition to encryption and physical security.

Unsanctioned devices

These are devices that are being used in the network without the approval or knowledge of management.

Often, employees innocently attach their personal devices like laptops and phones to the company's network. These devices present a danger because most if not all may not meet the company's standards across quality and security.

IT managers should not allow employees to use their personal devices at will. Some of these devices could be running on suspect operating systems which is a huge risk. It's okay to allow employees to bring some devices when they have to, but you need to set up BYOD policies to regulate their acceptance and use.

IoT devices

The Internet of Things (IoT) refers to the network of physical devices that are connected to the internet. For your company’s network, this could include everything from smart thermostats and security cameras to machinery and vehicles. While the growing IoT ecosystem offers many gains, it also creates new security risks.

One of the biggest threats posed by IoT devices is that they can be used to gain access to the network. Hackers can exploit vulnerabilities in these devices to remotely control them or steal sensitive data. In addition, IoT devices generate a large amount of data that can be overwhelming for security systems to protect.

Be sure to buy all IoT devices from reputable vendors and engage experienced IoT companies to verify that these devices have the right updates and firmware. If possible, please separate the IoT devices and run them in a secondary network that is completely detached from the main one.

Wi-Fi

Wi-Fi networks are becoming increasingly common in workplaces, but they can also create vulnerabilities that could be exploited by cyber criminals. One of the biggest risks is that Wi-Fi networks can be easily accessed by anyone within range, including people who are not authorized to be on the network. This means that sensitive data could be intercepted as it is being transmitted between devices.

Another vulnerability is that Wi-Fi networks can be used to launch so-called 'man-in-the-middle' attacks, whereby an attacker gains access to a communication between two devices and can eavesdrop on or even manipulate the data being exchanged.

Observe these best practices for Wi-Fi access in your network:

• Never set up Wi-Fi access points without a password. Anyone in close range can access it. Additionally, criminals can access both inward and outward traffic since the Wi-Fi is unencrypted as a result of lacking a password.
• Avoid displaying Wi-Fi passwords on walls. Anyone with malicious intentions can simply walk into the office pretending to be a visitor, get the password and spoof the network.
• Ensure that each part of the premises has a strong internet. Otherwise employees can easily resort to creating their own Wi-Fi hotspots, which is risky.

Firewall vulnerabilities

As you know firewall devices are extremely essential for protecting the network from outside intrusion. The firewall routers are particularly used to segment a network into different zones, and each zone has its own firewall. By default, all traffic is blocked from entering a network unless it is specifically allowed by the firewall.

However, criminals can use firewall devices to gain entry into the company's network by exploiting weaknesses in the configuration of the firewall. For example, if the firewall is not properly configured, it may allow data packets to be routed through the network without being checked by the firewall. This can allow criminals to gain access to sensitive information or even take control of the entire network.

The trend these days is web application firewalls (WAFs), a departure from the traditional firewalls. The web application firewalls can monitor patterns round the clock and automatically and block requests that show signs of attacks.

Please note that it's much more secure to have more than one firewall. This way you can then segment the internal networks and dedicate a secondary firewall to the segment that contains sensitive data.

Also on Firewalls: Best small business firewalls

Forgotten devices

These are devices attached to the network, but no one including the IT managers seems to know of their existence. It could be a laptop of a former employee forgotten in some corner, a tablet, or even a server. Since these devices are not actively monitored, attackers can easily take control of them and configure them to infiltrate the network.

Solving this is easy: Simply take regular inventory of all devices in the network. Disable those that are not active and keep them in a secured place.

Here are a couple other forms of different hardware vulnerabilities and the damage they can cause.

• Directory traversal: Occurs as a result of flaws in old or obsolete routers. These flaws make it easy for criminals to take over the routers and use them to extract important administrative data.
• Rowhammer: Rowhammer vulnerabilities affect DDR DRAM devices, where a memory can be accessed many times and cause bit flips within adjustment rows. This then allows hackers to interfere with the values of the memory’s bit.
• Foreshadow: Foreshadow is a vulnerability that is associated with Intel CPUs. Hackers exploit this vulnerability to gain access and get away with sensitive data from the L1 data cache of the CPU.

Hardware manufacturers are always working to reduce the number of hardware vulnerabilities in their products, but these vulnerabilities will always be a headache. So take care.

Example: The Mirai botnet attack, 2016

The best example of where hardware vulnerabilities can be exploited to large scale damage is the Mirai botnet attack that happened in October of 2016, the largest of its kind. It left an imprint of destruction, but not without a silver lining — a wake-up call for the security community. The attack was made possible by hardware vulnerabilities in IoT devices, which the attackers exploited to create a massive DDoS (distributed denial of service).

The Mirai botnet, a new weapon at the time, trained its guns at the networks of Dyn, an American DNS service provider that was later acquired by Oracle. The damage was far and wide, affecting major sites including Amzaon.com, Netflix, GitHub, Spotify, Quora, Reddit, Twitter and indeed Dyn's own website.

The attackers infected a network of vulnerable IoT devices with a special kind of malware named “botnet”. They then coordinated the infected devices to bombard the servers of Dyn with traffic until they collapsed under the strain.

Over 500,000 devices infected

The Internet of Things (IoT) concept was not nearly as obvious back in 2016 as it is now. It was a little new then, a technology largely at hype phase which only a few had a hang on. This made the Mirai attack even more intriguing.

Intriguing in the sense that while other botnets normally originated from a network of computers, the Mirai botnet caught companies flat footed as it was largely driven by IoT devices: DVR players, air-quality monitors, home routers, digital cameras and more IoT. Conservative estimates show that Mirai infected over 500,000 vulnerable IoT devices at its peak.

These kinds of attacks are only going to become more common as more and more devices are connected to the internet. So, what can you do to make sure your network is secure? Make sure you're patching your devices regularly, using strong passwords and changing default settings. You should also be aware of which devices in your network are susceptible and take steps to protect them.

How to prevent hardware network vulnerabilities

• Review hardware vendors: Seek to understand the security processes of all your hardware vendors. Do they have a good hold of their component suppliers? What is their security history? These details will help you to verify that the vendors will not supply you with vulnerable hardware as a result of their negligence. For example, ensure the manufacturer performs thorough laboratory tests for Trojan Circuits prior to deploying the final product.
• Hardware Firewall: Deploy the right hardware Firewall for your hardware infrastructure depending on what devices you want to protect as well as the broadband router that you are using. Your router should also have an inbuilt Firewall, so please ensure that it is always active. Large organizations are better off using business networking Firewall.
• Shut down: Always Shut down your servers whenever they are not in use for a considerable period of time like overnight. In other words don't leave your web server running even when it's not in use. Unless your organization is in the business of providing internet-based services, it makes security sense to switch off your hardware during the time that it is not in use. Many businesses have the habit of leaving their machines on, a vulnerability that can lead to serious damage. Timely shut downs will break any connection that attackers may have established to your network, throwing them off balance and suspending their crooked operation.

2. Software network vulnerabilities

A software vulnerability is a flaw in the network system's software architecture that can allow an attacker to gain access and compromise the system. The vulnerabilities can be due to many factors and mostly in the design and source code architecture.

By software here we mean any software that you use in your network systems, from the operating systems to other additional software that you utilize. The most common software security loopholes include injection flows, broken access control, missing or broken authentication, misconfiguration, bugs, and buffer overflow.

Once an attacker succeeds in gaining access to the software that runs your network system, they can easily manipulate crucial data, damage it with botnets like in the example of the Mirai botnet DDoS, plant malware, or install a backdoor. Some attackers can also penetrate one network host and use it to cause havoc in more hosts running in the same network.

Here are the common categories of software network vulnerabilities:

Outdated software

When most people think of outdated software, they think of programs that are no longer supported by the manufacturer. However, outdated software can also refer to any program that is no longer receiving updates. This can include programs that are still supported but are several versions behind the latest release. While outdated software might not seem like a big deal, it can actually be a serious network vulnerability. Manufacturers frequently release updates for their software in order to prevent and also address security flaws that have been discovered, if any.

When a program is no longer being updated, any security flaws remain unpatched, making it easier for hackers to exploit them. Additionally, outdated software often lacks features that have been added to newer releases, making it less effective at performing its intended function.

Timely updates close these gaps and make it much harder for attackers to get into your system. Additionally, make a point of getting rid of all software that is no longer in use such as add-ons and plugins.

Unsanctioned software

This is similar to BYOD, where employees access and use software that has not been authorized for use in the workplace. Since the IT managers have neither knowledge nor control of this kind of software, those using it at work can innocently download malware into the network.

This vulnerability has become more prevalent in the era of cloud computing, where the next cool application is just a click away. The fact that so many applications come at no cost worsens this challenge.

Companies can avoid this problem by developing a shadow IT policy, which should also cover BYOD vulnerability that we covered under hardware vulnerabilities above.

Software configuration issues

You can have the best software that is updated to the latest version. But poor configuration can render this software effectively vulnerable. Pay attention to these areas:

• Default credentials: Never approve any software for use without changing the default credentials for files, directories and user accounts.
• Access levels: Analyze all default access privileges and restrict those that need to be restricted. It's common to find everyone in the company having the same access privileges as administrators. This is wrong.
• VPNs: VPN may be crucial for some departments within the company, but the wrong VPN configuration can let in attackers who will use the same VPN to access your network.
• Authentication: Weak authentication occurs when passwords are easy to guess. Please deploy multi factor authentication across the entire network. Don't compromise on this, simply implement it.

Coding errors

These are mistakes made during the coding process that can leave openings for attackers to exploit. These errors can cause the program to crash, produce incorrect results, or provide unexpected behavior.

The severity of these errors can vary, from trivial issues that have no impact on program functionality to critical vulnerabilities that can compromise the security of a system. For example, criminals can leverage an error that produces incorrect results to trick users into revealing confidential information.

Design flaws

Design flaws are errors in the way a software is designed that can make it susceptible to security vulnerabilities. These flaws can occur when developers fail to consider security during the design process, or when they make assumptions about how the software will be used that turn out to be false.

One example of a design flaw in software is a buffer overflow. This can happen when too much data is entered into a field that is not designed to hold it all. The excess data can then overflow into other parts of the software, corrupting it and potentially allowing attackers to take control.

Buffer overflows are just one example of how design flaws can create vulnerabilities in software. Poorly designed software can also be susceptible to SQL injection attacks, cross-site scripting attacks, and a variety of other types of attacks.

Top software vulnerabilities

The US Cybersecurity and Infrastructure Security Agency lists the top software vulnerabilities or cyber attacks that are routinely exploited from time to time.

Below is a summary of the top software vulnerabilities that were exploited across 2021.

Source: US Cybersecurity and Infrastructure Security Agency

Example: Aids Trojan by Dr. Joseph Popp

A good example of a software vulnerability was exposed by the first ever ransomware known as the Aids Trojan Horse, unleashed in 1989 by one Dr. Joseph Popp, a biologist. Joseph sent infected floppy diskettes to hundreds of innocent people. The title of the diskettes was so appealing, but the contents did the exact opposite. The title read, “Aids Information Introductory Diskette”.

As soon as a user inserted the diskette into their computer and played it, it automatically replaced the file AUTOEXEC.BAT and started counting the computer's number of boots. Once the number of boots clocked 90, the ransomware would then hide directories and encrypt all file names on the hard drive. This would render the entire system impossible to use.

Once the computer was unusable, the now “lost” victim would be instructed to renew their operating software license by sending $189 to an address in Panama, apparently belonging to an organization called ‘PC Cyborg Corporation”. Ironically, the decryption key was right there in the Trojan's code.

As you might have guessed by now, Dr. Joseph Popp collected some easy profits with the “clever” ransomware. He was eventually prosecuted, processed for trial, but was unfortunately declared mentally unfit to go through the trial. He concluded the mischief by promising to donate part of his profits towards research efforts into Aids.

How to prevent software vulnerabilities

• Train developers: Invest in training your developers to write impenetrable code, at least for the most critical areas if not everywhere in the software ecosystem. A base level security masterly will go a long way to defend your organization against catastrophic software vulnerabilities.
• Scan code: Use automated code scanning tools to scan your entire code for vulnerabilities. While no tool or combination of tools can discover each and every vulnerability, investing in code scanning will make a significant contribution to your network security.
• Testing: Test your software with code analysis tools to establish and quickly get rid of vulnerabilities.
• Regular updates: Make a point of updating your software regularly. Outdated software is a glaring vulnerability that attackers can discover and exploit to your downfall.
• Antivirus: Purchase and install the right antivirus software to protect your network against unauthorized code or programs. New viruses come up all the time, so it's important to ensure that the antivirus is always running whenever your systems are on. In addition, perform regular virus scans to keep your system free of viruses.

For a more comprehensive exploration of software vulnerabilities, including detailed insights and prevention strategies, check out our in-depth article: The Major Types of Software Vulnerabilities.

Understanding these software vulnerabilities is crucial for a holistic approach to network security.

3. Human error vulnerabilities

Human-based network vulnerabilities are those that are caused by human error. This can be anything from clicking on a phishing email to leaving your computer unlocked when you walk away.

A World Economic Forum Report reveals that indeed human error is the ultimate cause of nearly all cybersecurity vulnerabilities, accounting for an astonishing 95%. So you can clearly notice how serious this vulnerability can get. It means if you can work on human errors within your organization, you can somehow prevent at least 9 out of 10 cyber threats.

Human errors can be task based or decision based. Task based errors are those where a user makes simple but costly errors as result of negligence, fatigue, or insufficient skills. Decision based errors come about as a result of faulty decisions due to limited knowledge, scant information or inaction.

Example: Google and Facebook

The best example of the kind of attacks that can take advantage of human vulnerabilities is phishing. Big companies such as Google and Facebook have fallen victim to human error vulnerabilities and lost millions. The scammers took advantage of a vulnerability in the two companies' sourcing systems. Both Google and Facebook were using the services of a hardware vendor based in Taiwan, known as Qanta. The phishers released fake invoices to Google and Facebook. The invoices appeared just like the usual original invoices from Qanta, but of course they were all pure impersonations that employees of the two companies failed to detect. Google and Facebook, giants in the tech space, paid the phishers to a tune of US$100 million. Reason? human error. The main perpetrator of the scheme was eventually tried and surrendered US$49.7 million.

If the big corporations can fall prey to such seemingly simple vulnerabilities, no organization can claim to be safe. The best way to protect yourself from phishing attacks is to be vigilant and NEVER click on links or open attachments from unknown sources. Always make sure the website you're visiting is legitimate and has a secure connection (look for the HTTPS lock in your browser's address bar). You can also install anti-phishing software to help protect you from these attacks.

How to prevent human network vulnerabilities:

• Training: Be diligent about training your employees and make sure they understand the importance of security.
• Protocols: Have protocols in place for when an employee makes a mistake. For example, implement a protocol system that automatically locks the computer after a set amount of time or requires a password to unlock it.
• Tools: Use tools that alert your employees to double check certain actions where there is threat of high network risks. A good example is when they receive emails from vendors like the case of Google and Facebook where scammers faked emails from a supposed vendor and got paid millions. Use systems and structures that help employees to take each high impact communication through a strict verification system.

Network Vulnerabilities: Conclusion

To ensure network security, it's important to be aware of the major types of network security vulnerabilities that can exist. Hardware vulnerabilities are caused by a flaw in a physical device, software vulnerabilities are caused by a flaw in the software code, and human error vulnerabilities are caused by mistakes made by humans.

You can protect your network against these vulnerabilities by using security tools like firewalls and intrusion detection systems, utilizing the services of network security providers, and by training your employees on how to protect against these threats.