Breaking Weak Implementations of VPN Encryption and the Role of Entropy Levels

by Kate Libby

In the modern era, having the ability to work remotely, maintaining solid data security and privacy are paramount. Virtual Private Networks (VPNs) have become essential tools for safeguarding sensitive online communications. VPNs provide a secure and encrypted tunnel between a user's device and a remote server, ensuring that data remains confidential and protected from potential threats. However, not all VPNs and implementations are created equal. Weak implementations of VPN encryption can expose vulnerabilities that malicious actors can exploit, compromising the very security they are intended to provide. In this article, we delve into the intricacies of breaking weak implementations of VPN encryption and explore the pivotal role that entropy levels play in bolstering cryptographic strength.

To commence our exploration of breaking VPN encryption implementation, we initiated our own in-house VPN system utilizing the well-regarded OpenVPN framework. Our approach involved steering clear of any commercial or enterprise-level VPN setups in production environments, to avoid any potential risks or service disruptions. Our actions aimed to maintain caution while being confident that, given the vulnerabilities in commercial systems and weak implementations, we could attain results that are remarkably similar.

While more significant efforts have been channeled into reversing through proxies as opposed to VPNs, it was our experiment with proxies that paved the way for our investigation using a custom-created VPN within a controlled laboratory environment.

The primary objective of our experimentation, considering that we are not cryptography experts by profession, revolved around identifying and capitalizing on vulnerabilities within the....