[nashashmi]

> All of our VPN servers continue to use our custom and extensively slimmed down Linux kernel, where we follow the mainline branch of kernel development.

The custom server is a niche security point. While every server is continously researched and patched, we cannot expect the same from a a server like this. If someone were to find a security hole, an attacker would purchase it and no one else would ever know the system was compromised.