Article: ProtonVPN IP Leakage on Linux and Workaround | PrivSec - A practical approach to Privacy and Security Killswitch does not work with all network interfaces. Can you be tested using following command curl --interface <physical interface> https://ipinfo.io Suggestion add an additional not…

[image] Encounter5729: I would agree that this issue in itself obviously doesn’t in itself merits delistment. I’m going to mark this topic (which is specifically about adding a warning to Proton VPN about this issue) as approved , because I think it is fairly reasonable for us to do, and it se…

I would agree that this issue in itself obviously doesn’t in itself merits delistment. The question is whether the entirety of those issue does IMO.

[image] anon61138815: curl --interface <physical interface> https://ipinfo.io The real world impact of that is a misconfigured piece of software could circumvent the kill switch if it binds to the wrong interface. Bittorrent clients are one such example of that.

[image] jonah: think the question of whether we should have additional guidance/warnings about software kill switches in general probably belongs in a different topic or One already exists for that

[image] fiqiluvo.epileto: Qubes approach makes it possible to have a messy user facing OS while having a tight and predictable network VM. With Qubes, in the worst case scenario a user facing VM will loose connection. We can mimick this by disallowing the host OS to manage wwan and connect to t…

[image] ignoramous: It is my understanding that an external hardware gateway cannot act like a ‘killswitch’ if there’s no corresponding software-related killswitches installed / setup on the devices. I feel this is true but the point being brought up is that the external device cannot be inte…

[image] jonah: the point being brought up is that the external device cannot be interfered with by software running locally on your computer, resolving interface binding issues like this. Binding to an interface is the first thing ALL sockets (in the BSD APIs that Linux and BSDs and macOS use…

[image] ignoramous: I don’t get why there’s a sense here that Linux-based distros don’t provide anyway to setup a leak-proof killswitch (when the Linux kernel does via various sandboxing / filtering / in-kernel mechanisms) That is, if a user doesn’t supposedly tinker with routing in any way. …

I guess we can shift the discussion towards decoupling VPN services and VPN clients. With the existing killswitch criteria, PG couldn’t recommend service providers that rely on censorship evasion protocols as they were historically implemented as proxies due to different proxying strategy needs. Var…

[image] jonah: [image] ignoramous: It is my understanding that an external hardware gateway cannot act like a ‘killswitch’ if there’s no corresponding software-related killswitches installed / setup on the devices. [image] ignoramous: OSes do have a larger attack surface than a router…

[image] dngray: think you’re all missing the main point [image] fiqiluvo.epileto: A standalone router with slim and predictable dnsmasq, wireguard and firewall rules is waaay easier to manage and trust than a vpn client on a Desktop Linux OS. [image] fiqiluvo.epileto: I haven’t seen …

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ProtonVPN Additional note: Killswitch failure and IP Leakage on Linux

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lyricism (lyricism) March 13, 2026, 2:03pm 69

I mean Proton has already clarified and confirmed they were talking about their “network stack”, so no, it was just poor wording.

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ProtonVPN Additional note: Killswitch failure and IP Leakage on Linux

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