If you’re experiencing a blue screen crash related to OpenVPN in your VPN application, you’re not alone. This issue is a result of a vulnerability present in the OpenVPN driver, necessitating a patch from its source. Since countless VPN providers integrate the OpenVPN protocol, many Windows users face this critical error. In the following, we’ll discuss how to identify this problem and implement preventative measures to avoid severe PC crashes.
Understanding OpenVPN Crashes on Windows
OpenVPN has become a popular choice among VPN applications. However, a significant buffer overflow vulnerability was discovered in June 2025 in the OpenVPN data channel offload (DCO) driver, known as “ovpn-dco-win.” This flaw triggers blue screen of death (BSoD) crashes.
This incident isn’t isolated. Historical vulnerabilities in OpenVPN’s plugin architecture have often posed risks, allowing for remote code execution and privilege escalation. For instance, Microsoft identified four critical vulnerabilities in 2024—including CVE-2024-27459 and CVE-2024-24974—that compromised the Windows TAP driver, resulting in denial-of-service (DoS) scenarios.
If your VPN is set to start automatically with Windows, you could encounter these crashes unless you have updated to the latest OpenVPN client, “OpenVPN 2.7_alpha2″or newer. Ensure that your VPN provider includes these updates in their Windows client and make it a priority to update without delay.
The DCO driver is responsible for critical data packet functions such as encryption, decryption, and routing, which are executed by transitioning these tasks from user space to the Windows kernel. Unlike WireGuard, OpenVPN’s DCO operates within kernel space, and these close interactions with the operating system are often responsible for crashes.
Previous kernel-level malware incidents underscore the complexities tied to such vulnerabilities, as demonstrated by the CVE-2025-50054 vulnerability, where malformed packets result in crashes due to low-level memory errors.
How to Identify and Disable OpenVPN Drivers on Windows
If you do not utilize OpenVPN, consider disabling its drivers. Many VPN clients install their own drivers, so it’s important to ascertain which of these exist on your system.
To begin, open File Explorer and navigate to “C:\Windows\System32\Drivers.” Here, look for OpenVPN-related drivers, such as the DCO driver – “ovpn-dco.sys.”
In addition to the DCO driver, keep an eye out for sensitive OpenVPN drivers such as the TAP-Windows Adapter V9 (“tapwindows6.sys”), Wintun driver (“wintun.sys”), and named pipe interfaces (e.g., “\\.\pipe\openvpn”).
You can track these drivers in the Device Manager. Launch the Run command (Windows + R) and enter devmgmt.msc. From there, navigate to Network Adapters to find OpenVPN entries like DCO and TAP-Windows Adapter V9.
If you wish to view all hidden OpenVPN drivers on your system, open PowerShell with administrator privileges. Execute the following command:
Get-WmiObject Win32_SystemDriver | Where-Object { $_. Name -like "*ovpn*" -or $_. Name -like "*tap*" } | Select-Object Name, State, PathName, StartMode
Following this, consider uninstalling the OpenVPN application entirely and manually removing all associated drivers, as they can linger even after uninstallation.
If you use a VPN client like NordVPN or ExpressVPN and do not require OpenVPN, transitioning to WireGuard is recommended as an alternative.
Setting Access Restrictions on OpenVPN Drivers
Due to OpenVPN’s extensive integration with the operating system, it’s particularly susceptible to low-level bugs that can lead to significant issues. To mitigate potential damage, it’s possible to restrict access permissions for compromised OpenVPN drivers without needing to uninstall your VPN client.
Open PowerShell in administrator mode and enter the following command:
$driverPath = "C:\Windows\System32\drivers\ovpn-dco.sys" icacls $driverPath /inheritance:r icacls $driverPath /grant:r "SYSTEM:R" "Administrators:R" icacls $driverPath /deny "Everyone:W"
The above command effectively removes inherited permissions to prevent unauthorized access, while denying write access to all users—including malware—thus ensuring that any driver malfunctions do not compromise your system.
To deny access for other hidden drivers, rerun the command while updating the driver path to target the TAP-Windows Adapter V9, “tapwindows6.sys.”
Monitoring BSoD Instances Linked to OpenVPN Drivers
While OpenVPN releases patches promptly, many users lag in applying updates. To proactively manage and prevent crashes, download and install a utility called Blue Screen View.
When installed, open PowerShell in administrator mode and execute the following script, ensuring you replace $nirDir with the correct installation path for Blue Screen View. This script monitors recent crash dumps to flag any linked to OpenVPN-related drivers.
# Set path to your BlueScreenView directory (update if needed) $nirDir = "C:\Tools\BlueScreenView" # ← Change this to your actual path $csvPath = "$nirDir\bsod.csv" # Monitoring loop while ($true) { # Execute BlueScreenView in command-line mode and export to CSV Start-Process -FilePath "$nirDir\BlueScreenView.exe" -ArgumentList "/scomma `"$csvPath`"" -Wait # Import and analyze results $bsods = Import-Csv $csvPath -Header Dumpfile, Timestamp, Reason, Errorcode, Param1, Param2, Param3, Param4, CausedByDriver $recent = $bsods | Where-Object { ($_. Timestamp -as [datetime]) -gt (Get-Date). AddMinutes(-10) -and $_. CausedByDriver -match "ovpn|tap|wintun" } if ($recent) { Write-Warning "⚠️ BSoD caused by OpenVPN driver in the last 10 minutes!" $recent | Format-Table -AutoSize } else { Write-Host "✅ No recent OpenVPN-related BSoDs." } Start-Sleep -Seconds 600 # Delay 10 minutes before checking again }
The results window reveals whether OpenVPN-related BSoD events were detected recently.
Implementing Software Restriction Policies for OpenVPN Drivers
For those using Windows Pro or Enterprise editions, you can utilize software restriction policies via the Local Group Policy Editor to prevent OpenVPN drivers from running without your consent.
To access the Group Policy Editor, type “gpedit.msc” in the Run command. Navigate through the menu as follows: Computer Configuration → Windows Settings → Security Settings → Software Restriction Policies → Additional Rules.
Right-click the last item in the Additional Rules and choose New Path Rule.
In the pop-up window, paste the path of the driver. For this scenario, use the path for OpenVPN’s DCO driver. Set the rule to Disallowed, and then click Apply followed by OK. Repeat this process for each additional driver you wish to restrict.
Since OpenVPN maintains kernel space drivers that can persist even after application uninstallation, these drivers frequently cause Windows to crash during startup. By following the aforementioned strategies, you can mitigate these risks effectively. Are you considering a new VPN solution?
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