Сразу хотелось бы вставить часть комментария с HN:
"They also claim that it affects all VPN clients in the headline, yet so many such clients setup firewall rules to block traffic to/from the physical interface as they acknowledge in the write-up. Most of the VPNs that are claiming to hide your identity or where such cloaking is important tend to implement that. I'm sure plenty of setups don't have it enabled by default, but I think it would have been productive to document what percentage of leading personal/commercial and corporate VPN solutions have this enabled by default."

Если коротко, то у большинства нормальных VPN клиентов по умолчанию есть firewall, который делает эту атаку невозможной.