Proton VPN and ASUS router BE-88U issues

[secCrazy]

ASUS router (BE-88U) was working fine until last week and it just stopped connecting to internet. I use proton vpn and never had issues with it. Contacted ISP, Proton and ASUS. ISP and Proton said it is not their problem and suggested talking to ASUS.
So, the issue happens only when the VPN is turned on. Otherwise, I am able to access the internet. The last update of the firmware was in October 2025. I am using the stock firmware and *not* merlin. ASUS does mention that they will push security updates whenever there is one necessary. So, I am not sure whether a silent security update happened or not. ASUS is yet to confirm the issue. But, their support phone call has an option (option 9) that has a prerecorded message that their security update caused several routers to go offline. Their suggestion was to save settings, do a factory reset and restore settings. I have done that about 3 times. But, the VPN and router do not get along.

Is anyone having this issue with Proton VPN and ASUS router with the latest firmware update? The Firmware version is 3.0.0.6.102_39112, release date: 10/29/2025
Any solution will be much appreciated.

Thanks...

 

[RMerlin]

Wireguard or OpenVPN?

I have a Guest Wifi network connected to ProtonVPN using Wireguard here, works quite reliably. I can't really tell for OpenVPN however, since Asuswrt and Asuswrt-Merlin use very different OpenVPN implementations. However our Wireguard are quite similar, aside from me using a slightly newer version of the kernel/userspace code.

So, I am not sure whether a silent security update happened or not

Any firmware update would show up as a newer firmware version, and the router would have rebooted itself when applying it. So no, any update pushed by Asus wouldn't really be silent.