Is Windows firewall supposed to apply to WSL? I never expected that! I'm serious - I run a different firewall on my onlinux.
Can you confirm that WSL is supposed to be dealing with (the nightmare) of the windows firewall for internet access? How does fedora / ubuntu etc coordinate / know to do this?
It's somewhat unintuitive that a virtualized guest can circumvent the host's firewall/network stack when the guest doesn't have an explicitly bridged or passthrough'd physical adapter.
As for the parent, if it's a Microsoft product running on Windows and Windows has a firewall, I'd expect it to be an effective firewall, at least for the things Microsoft gives me.
Windows while Hyper-V is enabled runs atop Hyper-V VMM as a VM, same ways as Linux running as Xen Dom0.
WSL2 uses Hyper-V, so Windows running WSL2 is running on Hyper-V, not bare metal. Being a different VM than Windows “Dom0”, Linux Kernel in WSL2 would have direct connection to Hyper-V virtual ethernet switch. I think that’s what is happening.
Exactly this. If you're running WSL2 then you're in Hyper-V mode, which means Windows itself is also running virtualized. The WSL VM is a sibling of Windows on the hypervisor stack, not hosted inside of.
No one is disputing the definition of "leak(ing)" rather what traffic is being leaked, which is not VPN traffic as the title suggests and the Mullvad link clearly explains. edit: the title has since been modified.
Can you confirm that WSL is supposed to be dealing with (the nightmare) of the windows firewall for internet access? How does fedora / ubuntu etc coordinate / know to do this?