The Security Risks of Widespread VPN Vulnerabilities

The Security Risks of Widespread VPN Vulnerabilities
The Siliconreview
09 June, 2021

Virtual private networks (VPNs) are some of the most commonly used systems for secure remote access to corporate networks. However, these systems have a number of different security issues, including a large number of high-severity and actively exploited vulnerabilities.

For many organizations, managing the security risks associated with VPNs is not worth the effort. A better approach is to switch to a modern alternative, such as the secure remote access functionality built into a SASE cloud solution.

VPN Vulnerabilities are a Prime Target for Cybercriminals

With the recent surge in remote work, VPNs have become a critical component of many organizations’ business strategies. Employees working from home use these systems to gain access to the corporate network every day.

With this increased usage also comes greater attention from cybercriminals. VPNs are prone to vulnerabilities, and their increased importance has meant that these vulnerabilities are a leading target of cyberattacks.

In fact, the NSA has issued warnings about the active exploitation of VPN vulnerabilities by nation-state attackers. These attacks indicate that VPNs, a critical part of an organization’s remote work infrastructure and the gateways to their networks, also contain vulnerabilities that make them a target of well-funded and sophisticated cyber threat actors.

What Can Go Wrong?

The software in a VPN endpoint decides what users are allowed full access to the corporate network and which ones are not. Vulnerabilities in these VPN systems can create a number of different security problems for an organization.

  • Authentication Bypasses

A VPN is designed to provide legitimate users with access to the corporate network. This means that the VPN endpoint’s code is the only thing standing between a potential outside attacker and full access to the corporate network.

Vulnerabilities in this code could allow an attacker to bypass these defenses in a few ways. Exploitation of a vulnerability may allow an attacker to bypass the authentication process and gain direct access to the enterprise network. Alternatively, a vulnerability may allow employee credentials to be leaked, providing legitimate access through the VPN. Or, exploitation of the VPN may allow the attacker to force the VPN to take actions on the corporate network on the attacker’s behalf.

  • Traffic Sniffing

VPNs are designed to encrypt network traffic from the remote client machine to the VPN endpoint. This helps to protect this traffic against eavesdropping or potentially malicious modifications.

With vulnerabilities in the VPN software, an attacker may be able to run malicious code on the VPN endpoint itself, which has access to the network traffic after it has been decrypted by the endpoint. Without these protections, the attacker may be able to monitor or modify business traffic. This could result in a breach of sensitive data or enable further attacks by modifying the data flowing to and from remote users’ computers.

  • Denial of Service Attacks

With the surge in remote work inspired by the COVID-19 pandemic, VPNs have become a critical component of organizations’ daily operations. Each day, a significant portion of an organization’s workforce connects to corporate resources via a VPN.

With this reliance on VPNs comes the potential for extremely damaging Denial of Service (DoS) attacks. Exploiting a vulnerability in a VPN endpoint may allow an attacker to knock it offline with dramatic impacts on employee productivity.

Managing the Risk of Insecure Remote Access

Their large number of vulnerabilities is not the only security issue faced by VPN software. Even if these vulnerabilities did not exist, the design of VPNs means that the organizations using them face significant challenges with regard to network performance, scalability, and access control. Even at their best, VPNs are a poor secure remote access solution for the modern distributed enterprise.

For this reason, designing and implementing a patch management strategy for VPNs is not the most effective way to manage their security risks. A better approach is to rip and replace with a secure remote access solution that actually meets the needs of the modern enterprise.

SASE is an alternative secure remote access solution that eliminates the common security and performance challenges of VPNs. SASE is implemented as a network of cloud-based virtual appliances that integrate a full security stack with the network optimization functionality of SD-WAN.

This combination provides a secure, scalable, and high-performance remote access solution. SASE includes zero-trust network access (ZTNA) - also called software-defined perimeter (SDP) - which replaces the highly-permissive access controls of VPNs with case-by-case access decisions based on zero-trust principles. Additionally, the global distribution of SASE nodes and the optimization of traffic between them provides a distributed and high-performance WAN.

VPNs are a legacy remote access solution prone to major security issues and exploitation by cyber threat actors. Choosing a modern solution - especially one with managed service offerings for vulnerability management - is essential to minimizing enterprise cybersecurity risk.