17.07.25

Mitigating VPN Vulnerabilities

Virtual Private Networks and their Vulnerabilities

A virtual private network (VPN) is a type of technology that uses an encrypted connection to route internet traffic through a remote server, granting a user access to certain digital services while masking their online activity. Connecting to a VPN establishes a safe tunnel between a user’s device and the internet, making it seem as though they are browsing from the server’s original location and protecting their data from being intercepted by malicious parties. Over the years, VPNs have become a crucial cyber- security tool for many organisations, particularly those that permit employees to work from different locations and use public wi-fi networks.

Although VPNs are intended to benefit organisations by providing secure gateways to private IT infrastructure and simplifying remote access capabilities for staff, they must be launched correctly, adequately safeguarded and updated regularly to remain effective. Otherwise, they can end up becoming attack avenues for cyber-criminals rather than protective barriers. What’s worse, VPN vulnerabilities are on the rise. According to a report by IT company Cybersecurity Insiders, almost half (45%) of organisations experienced at least one attack that exploited VPN vulnerabilities in a 12-month period. As such, it’s imperative for organisations to clearly understand the cyber-security challenges tied to VPNs and take steps to mitigate them.

This article provides more information on key VPN vulnerabilities, their possible ramifications and the associated risk management measures organisations should consider.

Common VPN Vulnerabilities

Because VPNs provide a bridge between the internet and an organisation’s internal systems, they are an attractive target for cyber- criminals. Consequently, hackers have been increasingly exploiting VPN vulnerabilities to launch cyber-attacks. These vulnerabilities can stem from a range of factors, including:

• Poor encryption protocols – A VPN’s encryption standards play a major role in keeping users’ online activity and data private. Most sophisticated cyber-criminals can bypass VPNs with outdated encryption protocols, creating significant cyber- security exposures.
• Weak authentication mechanisms – In addition to poor encryption standards, minimal or otherwise weak authentication requirements can make it easier for hackers to infiltrate a VPN and its surrounding IT infrastructure through brute-force techniques.
• Software issues – An effective VPN requires routine software updates and proper patch management. When a VPN is left unpatched, this can lead to bugs, glitches and other technical problems, all of which increase the risk of a cyber-attack.
• Coding concerns – A VPN relies on accurate coding to operate as intended. If this code gets misconfigured, whether due to a system breakdown or human error, the VPN won’t function correctly, rendering it useless against cyber-criminals. outdated encryption protocols, creating significant cyber- security exposures.

Upon exploiting a company’s VPN vulnerabilities, cyber-criminals may be able to infiltrate its larger IT infrastructure, ultimately disrupting critical operations, creating possible supply chain complications and compromising confidential data. One example of this type of attack is the Travelex ransomware attack in 2019. Currency exchange firm Travelex was hit by a ransomware attack in which threat actors exploited a vulnerability – a software flaw that Travelex had failed to patch – in the firm’s VPN. The attackers stole sensitive information and demanded a ransom for its return. The company suffered months of disruptions and paid more than £2 million to the ransomware group.

Consequences of VPN Vulnerabilities

Cyber-attacks resulting from VPN vulnerabilities can pose a number of consequences, such as:

• Financial and reputational fallout – As with any cyber-attack, a VPN-related incident can cause substantial financial losses for the impacted organisation, especially when it involves compromised data, stolen corporate funds and prolonged operational disruptions. Depending on the nature and scale of the incident, it may also foster frustration and distrust among customers and other key stakeholders, resulting in considerable reputational damage.
• Legal and compliance issues – An organisation could encounter serious regulatory ramifications if certain types of sensitive data (eg stakeholders’ personally identifiable information, health records and financial details) are compromised in a VPN-related cyber-incident. In particular, the organisation could face penalties for breaking data privacy laws, such as the Data Protection Act 2018 and the UK General Data Protection Regulation, both during and in the immediate aftermath of the incident.
• Ongoing attacks – During a VPN-related cyber-incident, hackers may infect certain elements of the impacted organisation’s larger IT infrastructure with malware or other harmful bugs and viruses, paving the way for ongoing attacks. In many cases, VPN vulnerabilities lay the groundwork for cyber-criminals to deploy ransomware attacks, distributed denial-of-service events and man-in-the-middle incidents, each of which are known to cause major damage.

Risk Mitigation Strategies

Considering the potentially severe ramifications of VPN vulnerabilities, it’s essential for organisations to leverage effective risk management techniques. Here are some best practices for organisations to implement:

• Conduct risk assessments. First and foremost, organisations should review and document their unique cyber-risks, taking into consideration their key operations, essential services, sensitive data and digital assets. From there, organisations can better determine what type of VPN will be most effective for their particular circumstances.
• Select a trusted service provider. Organisations should carefully research different VPN service providers and choose one that fits their needs. Specifically, the provider should have a solid reputation and display a commitment to cyber-security. The best VPN service providers typically provide built-in encryption features and have no-logs policies, meaning they won’t store any data regarding users’ online activity. Some providers may even offer extra security features, such as kill switches for compromised programs or devices.
• Enable security features. Organisations should enable any security features available to strengthen their VPNs, including anti-malware programs, adblockers, multifactor authentication protocols and data leak prevention tools. In addition to the VPN software itself, these security features should be updated regularly. If possible, organisations should consider enabling automatic software and security updates or deploying patch management solutions to stay on track with such updates.
• Monitor network activity and perform audits. Various threat detection tools (e.g. endpoint detection and response solutions) can help organisations closely monitor their VPN connections and identify any unusual network activity in real time. These tools can allow organisations to address connection issues as swiftly as possible and respond to potential threats before they escalate to large-scale attacks. In conjunction with such tools, organisations should also perform routine security audits to help detect any ongoing VPN vulnerabilities (e.g. misconfigured code) and make adjustments as needed.
• Educate staff. Employees are often the first line of defence against cyber- attacks. With this in mind, organisations should educate their staff about proper VPN use. This includes creating strong passwords; using safe devices; and only accessing data, systems and services deemed critical to fulfilling their job roles. Organisations should also provide employees with ways to identify potential VPN vulnerabilities or suspicious network activity and outline how to respond if a VPN-related cyber-attack occurs.
• Consider alternatives. In some cases, VPNs may not be worth the risks they pose to organisations. Under these circumstances, organisations should consider alternative remote access solutions, such as zero-trust network access, virtual desktop infrastructure, secure access service edge, software-defined perimeters or privileged access management tools.

Conclusion

Even though VPNs can help organisations boost their cyber-security measures, they may create additional vulnerabilities. Left unmanaged, these vulnerabilities could easily be exploited by cyber- criminals. Fortunately, by upholding effective VPN security measures, organisations can minimise possible cyber-attack avenues and avoid costly losses.

Contact us today for more risk management guidance.

Information provided by Zywave with a contribution from Lisa Langley, Cert CII, Team Leader, Professional Risks, Cox Mahon Ltd.

This Cyber-risks & Liabilities document is not intended to be exhaustive nor should any discussion or opinions be construed as legal advice. Readers should contact legal counsel or an insurance professional for appropriate advice. © 2025 Zywave, Inc. All rights reserved.