According to an audit conducted in July 2026, 56% of Windows VPN applications use OpenVPN code that is more than a year old, leaving users exposed to unpatched vulnerabilities. Premium providers like NordVPN, Windscribe, and Proton VPN have adopted recent releases, but older configurations across the industry present significant security and compatibility risks.
Outdated OpenVPN Versions Plague Windows VPN Apps
A comprehensive examination of 32 Windows VPN applications conducted in July 2026 revealed that more than half of the tested software relies on stagnant encryption protocols. According to the audit data, 56% of the applications—18 out of 32—run OpenVPN versions older than 12 months. The findings highlight a severe lag in security maintenance across both major multinational providers and smaller developers.
The age of the underlying code scales dramatically across the tested pool. The audit found that 41% of applications, or 14 programs, utilize configurations older than two years. Furthermore, 22% of the tested apps rely on code exceeding four years of age, while 12.5% run software that is at least five years old. For instance, services like Turbo VPN and VyprVPN still utilize OpenVPN 2.4.7, a version released in April 2019.
Did you know? While many VPN providers regularly update their user interfaces and bug trackers, the core OpenVPN components bundled into the software often remain untouched for years.
Security Risks of Running Legacy OpenVPN Code
OpenVPN serves as the de facto open-source standard for encrypting and routing data between user devices and servers. However, running legacy versions strips users of critical upstream security fixes. According to Marijus Briedis, CTO at NordVPN, running a version that trails behind by years means missing out on routine patches, basis code fortifications, and performance enhancements.
Jason Xu, a senior application developer at Windscribe, notes that older vulnerabilities actually become more dangerous over time because they are thoroughly documented. “An attacker even needs to find no new bug; they can read the changelog,” Xu stated.
Official data from OpenVPN underscores the steady stream of discovered flaws. The project recorded six Common Vulnerabilities and Exposures (CVE) in 2025, another six in 2024, one in 2023, and one in 2022. Providers failing to adopt upstream releases miss these critical patches. Beyond security patches, Dr. Peter Membrey, Chief Research Officer at ExpressVPN, pointed out that older versions accumulate technical debt, making them increasingly difficult to integrate with modern operating systems and cryptographic libraries.
Why VPN Providers Delay Protocol Updates
Upgrading to a new OpenVPN release is a complex engineering task. According to industry engineers, rolling out a fundamental protocol change requires extensive cross-platform compatibility testing, regression checks, and phased deployments. NortonVPN, which is currently transitioning to the newest OpenVPN version, explained that every update demands careful evaluation to ensure it brings clear benefits without breaking stability or performance.
Karolis Kaciulis, a leading system engineer at Surfshark, noted that a delay of six to 18 months remains reasonable as long as critical vulnerabilities receive immediate attention. Individual providers offered varied operational reasons for their timelines. StrongVPN stated that internal protocol development delayed its move to OpenVPN 2.7. ClearVPN reported applying custom security patches to its existing framework, while PureVPN maintained OpenVPN 2.6.12 to support custom technologies tied to that version, as OpenVPN 2.7 removes support for Wintun drivers.
Shifting Industry Standards and How to Audit Your VPN
Faced with the maintenance burdens of legacy OpenVPN deployments, many providers are pivoting toward WireGuard as a default, more actively maintained protocol. Some companies are actively phasing out OpenVPN on client apps altogether. Proton VPN, for example, is dropping client-side OpenVPN support while keeping it active solely for routers and legacy devices.
Pro Tip: Users can audit their current VPN setup by inspecting client settings, diagnostic logs, or official release notes. Any core protocol dependency older than 12 to 18 months without documented justification is a red flag indicating delayed security patches.
Frequently Asked Questions
What is OpenVPN and why does its version matter?
OpenVPN is an open-source protocol responsible for encrypting and securing data traffic between a device and a VPN server. Running outdated versions means missing out on newly patched security vulnerabilities and modern operating system compatibility.
Do all outdated VPN apps put users at immediate risk?
Not necessarily. While running older code introduces unpatched risks, the actual threat depends on whether the provider has backported security patches or mitigated specific vulnerabilities independently.
Which VPN services currently use updated OpenVPN versions?
Recent industry audits show that premium providers such as NordVPN, Windscribe, and Proton VPN utilize recent OpenVPN releases.
How can I check which OpenVPN version my VPN uses?
Users can verify their VPN’s protocol version by reviewing the application’s diagnostic logs, settings menus, or official release documentation.
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