Microsoft confirmed that the latest Windows security update, KB5036893, may cause VPN connection failures for Windows devices running Windows 11 and Windows 10 versions 23H2, 22H2, and 21H2.
[https://learn.microsoft.com/en-us/windows/release-health/status-windows-11-23H2#3291msgdesc]
[https://support.microsoft.com/en-us/topic/april-9-2024-kb5036893-os-builds-22621-3447-and-22631-3447-a674a67b-85f5-4a40-8d74-5f8af8ead5bb]
Microsoft is working on a fix, which will be rolled out in a future release.
If you are a VPN user and have installed the affected update, your VPN connections may be at risk. You can attempt to uninstall the update, but keep in mind that security updates are rolled out for a reason. Only uninstall the update if you are aware of the risks and your VPN is unusable.
Alternatively, ensure that your VPN's kill switch is enabled to prevent your internet connection from being exposed outside of the encrypted VPN tunnel if your VPN connection drops.