10 Most Common Network Vulnerabilities

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Today organizations need to be aware of the most common cyber risks threatening their networks. If you’re not taking proactive steps to protect your network, you’re leaving yourself open to powerful automated attacks. In this blog post, we will present a detailed list of the most common network vulnerabilities, defining first what a network vulnerability is, then explaining 10 of the most common network vulnerabilities, from outdated software and single-factor authentication to shadow IT security vulnerabilities.

What are network vulnerabilities?

A network vulnerability is a weakness or flaw in a network that can be exploited to gain unauthorized access and launch any kind of attack. Network weaknesses or flaws can reside in hardware, software, or configuration settings, thus requiring a comprehensive security strategy to effectively address them.

Common network vulnerabilities

1. Insecure wireless networks

When configured by default or with a weaker, obsolete security protocol such as WEP or WPA2 PSK (pre-shared key), any wireless access points will appear to outside attackers as an open invitation to launch malware, data theft, or security breach attacks. To avoid this, only connect to secure wireless networks that are using the WPA2 protocol, through a Virtual Private Network (VPN), and using two-factor authentication. Also, make sure to encrypt all data transmitted over the network.

2. Removable media devices

Removable media devices such as USB drives, memory cards, CDs, and DVDs can introduce malware to your network if they are not properly scanned for viruses or other malicious content. To avoid this, scan all removable media devices before connecting them to any networked computers and disable autorun features. Additionally, encrypt all confidential data stored on removable media devices in case they are lost or stolen, and enforce strict policies on their use. Other measures include using only read-only devices, physically securing them, and monitoring their use with removable media management software.

3. Outdated software

Outdated software is one of the most common but also one of the easiest to exploit. For security purposes, software developers regularly release software patches to address any security weaknesses, bugs, or errors found in the previous versions of their applications. When software is outdated, it means that security patches have not been applied and that there are publicly known exploits which attackers can easily exploit, either remotely or locally. The larger the application is, the wider is the attack perspective for attackers. The daily release of patches by organizations such as Google, Apple, and Facebook is very telling of how vulnerable to attacks outdated or unpatched applications are.

4. Weak passwords

If you’re using a weak or default password, chances are your network is already compromised. A strong password is at least 8 characters long and includes a mix of uppercase and lowercase letters, numbers, and symbols. The longer and more complex the password is, the harder it is to crack. Attackers use multiple methods to discover passwords, from social engineering techniques to brute-force attacks. Implementing strong password security policies – including a password strength meter, multi-factor authentication methods, and a password manager – is among the best ways to mitigate this network vulnerability.

5. Single-factor authentication

Single-factor authentication refers to authentication methods that only require one factor, typically a password or a PIN code. This network vulnerability can be easily exploited by attackers through social engineering techniques or by simply guessing the right password. In order to mitigate this network vulnerability, organizations should implement two-factor authentication (2FA) or multi-factor authentication (MFA). 2FA adds in an extra layer of security by requiring a second factor, such as a one-time code that is sent to the user’s mobile phone. MFA is considered to be the most secure authentication method as it is much harder for attackers to guess or steal all the required factors.


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6. Poor firewall configurations

Gartner Research states that misconfigurations are causing 95% of all firewall breaches. A firewall is a network security system that controls the incoming and outgoing traffic of a network. It is used to block off or allow certain types of traffic based on predefined rules. The growing complexity in firewall management in larger organizations can lead to human error and misconfigured firewalls. For instance, among the firewall network settings is “eq” (“equal to”), a parameter enabling access to a single, specified port, as opposed to “neq” (“not equal to”), enabling access to absolutely all the available ports. The typo of a mere “n” can shift an entire traffic path from very stringent and modest to widely open and massive.

7. Absence of data backups

This isn’t a network security vulnerability in itself, but, not having any offsite data backups makes your network extremely vulnerable to an attack. In the event of a ransomware attack or a natural disaster, an offsite backup of your network data will allow you to easily restore your systems, avoiding any costly downtime or disruptions. There are multiple cloud storage providers that offer secure and reliable offsite backups. Organizations should also consider implementing redundancy measures, such as having multiple copies of data in different secure locations. Regular offsite backups of your critical data should also be part of a comprehensive cybersecurity disaster recovery plan.

8. Insecure incoming emails

One of the most common network security issues is email-based attacks. These attacks can take many forms, but the most common is phishing. Phishing is a type of email attack that uses fraudulent emails to trick users into revealing sensitive information such as passwords or credit card numbers. Attackers can also use phishing emails to install and spread out malware over an organization’s network. To protect yourself from phishing attacks, be suspicious of any email that asks you to click on a link or download an attachment. To avoid any member of your personnel to become the weakest link in your network, give them a cybersecurity awareness & phishing test training. This will help prevent those email clicks to lead to a widespread and costly malware attack.

If you are unsure about the authenticity of an email, contact the sender to verify it before taking any further action. Another way to prevent any dangerous clicks is to hover over the link to see where it will take you before actually clicking on it. If the URL looks suspicious, do not click on it.

9. Mobile device

Mobile devices are increasingly being used to access corporate networks, namely through Bring Your Own Device (BYOD) policies. This can be a security issue because mobile devices may not have the same level of security features as computers, such as an antivirus or a firewall. Additionally, mobile devices can be easily lost or stolen, giving attackers direct access to sensitive data; and they are often connected to free public Wi-Fi networks, which security risks are numerous.

Mobile devices connected to a Wi-Fi network can give attackers an ideal environment to exploit them, namely for phishing, mobile ransomware, malicious applications and websites, and Man-in-the-Middle attacks.

10. Shadow IT

Shadow IT refers to any systems, applications, or services that were installed without prior authorization from the designated representative of the organization’s IT department. These systems have not thus been monitored and managed properly, nor have they undergone any form of security testing. Moreover, a lack of resources affecting the IT department may further escalate this risk for organizations relying on such unauthorized installed services.

Some of the measures to avoid shadow IT risks are as follows:

  • Making sure you’ve implemented a corporate policy clearly defining the use of IT systems.
  • Maintaining user education and training, which includes communication with your employees on how to protect against top network vulnerabilities.
  • Performing a network vulnerability assessment or regular vulnerability scanning while also fixing any identified issues promptly.

Final word

Network vulnerabilities can have a big impact on your organization, both for its reputation and bottom line. To protect your network and data, it is important to be aware of the most common network security risks and to take proactive measures to mitigate them. These include implementing proper authentication measures, encrypting sensitive data, and regularly backing up data. Additionally, it is important to educate your employees about network security risks and best practices. Regular penetration testing of your networks can also help secure your systems against ever-increasing sophisticated threats.

Contact us if you need help improving your network security.

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