Mirrored network mode not working in Win11 23H2, no network access

### Windows Version

Microsoft Windows [Version 10.0.22631.6491]

### WSL Version

2.5.10.0

### Are you using WSL 1 or WSL 2?

- [x] WSL 2
- [ ] WSL 1

### Kernel Version

6.6.87.2-1

### Distro Version

Ubuntu 22.04.5 LTS

### Other Software

_No response_

### Repro Steps

PS C:\WINDOWS\system32> wsl --shutdown
PS C:\WINDOWS\system32> wsl
wsl: Der gespiegelte Netzwerkmodus wird nicht unterstützt: Windows-Version 22631. 6491 verfügt nicht über die erforderlichen Features..
Fallback auf NAT-Netzwerk.
root@BHLC5U6W:/mnt/c/WINDOWS/system32# ip a
1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1250 qdisc mq state UP group default qlen 1000
link/ether 00:15:5d:28:d8:b6 brd ff:ff:ff:ff:ff:ff
inet 172.21.27.117/20 brd 172.21.31.255 scope global eth0
valid_lft forever preferred_lft forever
root@BHLC5U6W:/mnt/c/WINDOWS/system32# ping localhost
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.029 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.023 ms
^C
--- localhost ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1017ms
rtt min/avg/max/mdev = 0.023/0.026/0.029/0.003 ms
root@BHLC5U6W:/mnt/c/WINDOWS/system32# ip route show
default via 172.21.16.1 dev eth0 proto kernel
172.21.16.0/20 dev eth0 proto kernel scope link src 172.21.27.117
root@BHLC5U6W:/mnt/c/WINDOWS/system32# ping 172.21.16.1
PING 172.21.16.1 (172.21.16.1) 56(84) bytes of data.
^C
--- 172.21.16.1 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2028ms

root@BHLC5U6W:/mnt/c/WINDOWS/system32# nslookup www.google.com
;; communications error to 172.21.16.1#53: timed out
;; communications error to 172.21.16.1#53: timed out
^C
root@BHLC5U6W:/mnt/c/WINDOWS/system32#
logout
PS C:\WINDOWS\system32> nslookup www.google.com
Server: FRDS406.automotive-wan.com
Address: 10.216.0.9

Nicht autorisierende Antwort:
Name: www.google.com
Addresses: 2a00:1450:4001:804::2004
142.251.140.164

PS C:\WINDOWS\system32> ping 10.216.0.9

Ping wird ausgeführt für 10.216.0.9 mit 32 Bytes Daten:
Antwort von 10.216.0.9: Bytes=32 Zeit=18ms TTL=60
Antwort von 10.216.0.9: Bytes=32 Zeit=18ms TTL=60
Antwort von 10.216.0.9: Bytes=32 Zeit=16ms TTL=60

Ping-Statistik für 10.216.0.9:
Pakete: Gesendet = 3, Empfangen = 3, Verloren = 0
(0% Verlust),
Ca. Zeitangaben in Millisek.:
Minimum = 16ms, Maximum = 18ms, Mittelwert = 17ms
STRG-C
PS C:\WINDOWS\system32> wsl
root@BHLC5U6W:/mnt/c/WINDOWS/system32# ping 10.216.0.9
PING 10.216.0.9 (10.216.0.9) 56(84) bytes of data.
^C
--- 10.216.0.9 ping statistics ---
8 packets transmitted, 0 received, 100% packet loss, time 7157ms

root@BHLC5U6W:/mnt/c/WINDOWS/system32#

### Expected Behavior

Mirrored Network Mode working
Network access in WSL shell working other than to localhost
e.g. ping to gateway or DNS IP, nslookup

### Actual Behavior

Mirrored Network Mode not working, fallback to NAT
Network access in WSL shell not working (only ping localhost)
In WSL shell timeouts with pings to gateway or DNS IP, nslookup, wget

### Diagnostic Logs

[networking3.txt](https://github.com/user-attachments/files/25266882/networking3.txt)
[WslLogs-2026-02-12_11-02-20.zip](https://github.com/user-attachments/files/25266883/WslLogs-2026-02-12_11-02-20.zip)

Start by reviewing networking3.txt and the WslLogs archive, then reproduce the listed commands on Windows 10.0.22631.6491 with WSL 2.5.10.0 and Ubuntu 22.04.5. Done means mirrored networking no longer falls back to NAT and WSL can reach the gateway, DNS server, and external addresses.

Written by the indexing model from the issue text.