Share a Windows SOCKS5 proxy with an Ubuntu VMware guest using VMnet8 port forwarding (Tuxler VPN)

share-windows-socks-proxy-with-ubuntu-vmware(1).md

Share a Windows-Only SOCKS Proxy with an Ubuntu VMware Guest

This guide shows how to make a SOCKS5 proxy running on the Windows host available to an Ubuntu virtual machine using VMware NAT.

It is useful when:

• The Windows application exposes a local SOCKS5 proxy such as 127.0.0.1:23321.
• The Ubuntu guest cannot connect to the Windows host's loopback address.
• You only need selected applications in Ubuntu to use the proxy.

This does not create a full-device VPN inside Ubuntu. Only applications configured to use the SOCKS proxy will be routed through it.

Tested layout

• Host: Windows
• Guest: Ubuntu
• Hypervisor: VMware Workstation or Player
• VMware networking mode: NAT (VMnet8)
• Host-side SOCKS proxy: 127.0.0.1:23321
• Forwarded VMware-facing port: 23322

Change the ports below if your local proxy uses different values.

---

1. Confirm the SOCKS proxy works on Windows

Open PowerShell and run:

curl.exe --proxy socks5h://127.0.0.1:23321 https://api.ipify.org

The result should be the proxy exit IP rather than the host's ordinary public IP.

To compare it with the direct connection:

curl.exe https://api.ipify.org

If both commands return the same address, the local SOCKS proxy may not be active.

---

2. Keep the Ubuntu VM on VMware NAT

In the VM settings:

1. Open Network Adapter.
2. Select NAT: Used to share the host's IP address.
3. Enable Connected.
4. Enable Connect at power on.

Do not use Bridged mode for this setup.

---

3. Forward the local SOCKS port to VMware's NAT interface

Run the following in PowerShell as Administrator:

$vmwareInterface = 'VMware Network Adapter VMnet8'
$localSocksPort = 23321
$forwardedPort = 23322

$vmwareHostIp = (
    Get-NetIPAddress `
        -InterfaceAlias $vmwareInterface `
        -AddressFamily IPv4 `
        -ErrorAction Stop |
    Where-Object {
        $_.AddressState -eq 'Preferred' -and
        $_.IPAddress -notlike '169.254.*'
    } |
    Select-Object -First 1 -ExpandProperty IPAddress
)

if (-not $vmwareHostIp) {
    throw 'Could not find the IPv4 address assigned to VMnet8.'
}

Set-Service iphlpsvc -StartupType Automatic
Start-Service iphlpsvc

netsh interface portproxy delete v4tov4 `
    listenaddress=$vmwareHostIp `
    listenport=$forwardedPort `
    protocol=tcp 2>$null | Out-Null

netsh interface portproxy add v4tov4 `
    listenaddress=$vmwareHostIp `
    listenport=$forwardedPort `
    connectaddress=127.0.0.1 `
    connectport=$localSocksPort `
    protocol=tcp

Get-NetFirewallRule `
    -DisplayName 'SOCKS proxy for VMware' `
    -ErrorAction SilentlyContinue |
Remove-NetFirewallRule

New-NetFirewallRule `
    -DisplayName 'SOCKS proxy for VMware' `
    -Direction Inbound `
    -Action Allow `
    -Protocol TCP `
    -LocalAddress $vmwareHostIp `
    -LocalPort $forwardedPort `
    -RemoteAddress LocalSubnet `
    -Profile Any | Out-Null

Write-Host ""
Write-Host "Ubuntu SOCKS proxy: socks5h://${vmwareHostIp}:$forwardedPort"
Write-Host ""

netsh interface portproxy show all

The script prints an address similar to:

Ubuntu SOCKS proxy: socks5h://192.168.xxx.1:23322

Use the address shown on your own system. Do not copy the example address literally.

Compact one-liner

$if='VMware Network Adapter VMnet8';$src=23321;$dst=23322;$ip=(Get-NetIPAddress -InterfaceAlias $if -AddressFamily IPv4 -ErrorAction Stop|Where-Object {$_.AddressState -eq 'Preferred' -and $_.IPAddress -notlike '169.254.*'}|Select-Object -First 1 -ExpandProperty IPAddress);if(!$ip){throw 'VMnet8 IPv4 address not found'};Set-Service iphlpsvc -StartupType Automatic;Start-Service iphlpsvc;netsh interface portproxy delete v4tov4 listenaddress=$ip listenport=$dst protocol=tcp 2>$null|Out-Null;netsh interface portproxy add v4tov4 listenaddress=$ip listenport=$dst connectaddress=127.0.0.1 connectport=$src protocol=tcp;Get-NetFirewallRule -DisplayName 'SOCKS proxy for VMware' -ErrorAction SilentlyContinue|Remove-NetFirewallRule;New-NetFirewallRule -DisplayName 'SOCKS proxy for VMware' -Direction Inbound -Action Allow -Protocol TCP -LocalAddress $ip -LocalPort $dst -RemoteAddress LocalSubnet -Profile Any|Out-Null;Write-Host "Ubuntu SOCKS proxy: socks5h://${ip}:$dst";netsh interface portproxy show all

---

4. Test the forwarded proxy from Ubuntu

Replace VMNET8_HOST_IP with the address printed by PowerShell:

curl --proxy socks5h://VMNET8_HOST_IP:23322 https://api.ipify.org
echo

Example format:

curl --proxy socks5h://192.168.xxx.1:23322 https://api.ipify.org
echo

The result should match the IP returned by this Windows command:

curl.exe --proxy socks5h://127.0.0.1:23321 https://api.ipify.org

Use socks5h rather than socks5 when possible so DNS lookups are also performed through the proxy.

---

5. Use the proxy in Ubuntu

Current terminal session

export ALL_PROXY="socks5h://VMNET8_HOST_IP:23322"
export all_proxy="$ALL_PROXY"

Test it:

curl https://api.ipify.org
echo

Remove the variables later with:

unset ALL_PROXY all_proxy

Chromium

chromium --proxy-server="socks5://VMNET8_HOST_IP:23322"

Google Chrome

google-chrome --proxy-server="socks5://VMNET8_HOST_IP:23322"

Firefox

Open:

Settings → Network Settings → Settings

Set:

Manual proxy configuration
SOCKS Host: VMNET8_HOST_IP
Port: 23322
SOCKS v5: enabled
Proxy DNS when using SOCKS v5: enabled

---

6. Confirm which traffic is proxied

Direct traffic:

env -u ALL_PROXY -u all_proxy curl https://api.ipify.org
echo

Proxied traffic:

curl --proxy socks5h://VMNET8_HOST_IP:23322 https://api.ipify.org
echo

The two addresses should normally differ.

---

Stop or disable the setup quickly

To remove the Windows port-forwarding rule and its firewall rule, open PowerShell as Administrator and run:

$ip = (
    Get-NetIPAddress `
        -InterfaceAlias 'VMware Network Adapter VMnet8' `
        -AddressFamily IPv4 |
    Where-Object {
        $_.AddressState -eq 'Preferred' -and
        $_.IPAddress -notlike '169.254.*'
    } |
    Select-Object -First 1 -ExpandProperty IPAddress
)

netsh interface portproxy delete v4tov4 `
    listenaddress=$ip `
    listenport=23322 `
    protocol=tcp

Get-NetFirewallRule `
    -DisplayName 'SOCKS proxy for VMware' `
    -ErrorAction SilentlyContinue |
Remove-NetFirewallRule

Quick one-liner

$ip=(Get-NetIPAddress -InterfaceAlias 'VMware Network Adapter VMnet8' -AddressFamily IPv4|Where-Object {$_.AddressState -eq 'Preferred' -and $_.IPAddress -notlike '169.254.*'}|Select-Object -First 1 -ExpandProperty IPAddress);netsh interface portproxy delete v4tov4 listenaddress=$ip listenport=23322 protocol=tcp;Get-NetFirewallRule -DisplayName 'SOCKS proxy for VMware' -ErrorAction SilentlyContinue|Remove-NetFirewallRule

Confirm the forwarding rule is gone:

netsh interface portproxy show all

Inside Ubuntu, clear proxy environment variables from the current shell:

unset ALL_PROXY all_proxy HTTP_PROXY HTTPS_PROXY http_proxy https_proxy

Also:

• Close browser instances launched with --proxy-server.
• Remove any manual SOCKS settings from Firefox or other applications.
• Closing the Windows proxy application stops traffic temporarily, but the Windows forwarding rule remains until you remove it with the command above.

---

7. Remove the forwarding rule

Run PowerShell as Administrator:

$vmwareInterface = 'VMware Network Adapter VMnet8'
$forwardedPort = 23322

$vmwareHostIp = (
    Get-NetIPAddress `
        -InterfaceAlias $vmwareInterface `
        -AddressFamily IPv4 |
    Where-Object {
        $_.AddressState -eq 'Preferred' -and
        $_.IPAddress -notlike '169.254.*'
    } |
    Select-Object -First 1 -ExpandProperty IPAddress
)

netsh interface portproxy delete v4tov4 `
    listenaddress=$vmwareHostIp `
    listenport=$forwardedPort `
    protocol=tcp

Get-NetFirewallRule `
    -DisplayName 'SOCKS proxy for VMware' `
    -ErrorAction SilentlyContinue |
Remove-NetFirewallRule

Check that it has been removed:

netsh interface portproxy show all

---

Troubleshooting

Connection refused from Ubuntu

Confirm that the local SOCKS proxy is listening on Windows:

Get-NetTCPConnection -LocalPort 23321 -State Listen

You can also check with:

netstat -ano | findstr :23321

Then confirm the forwarded port is listening:

Get-NetTCPConnection -LocalPort 23322 -State Listen

The Windows proxy works, but Ubuntu cannot connect

Check:

netsh interface portproxy show all
Get-Service iphlpsvc
Get-NetFirewallRule -DisplayName 'SOCKS proxy for VMware'

The IP Helper service should be running.

The VMnet8 IP changed

VMware can change the address assigned to VMnet8. Re-run the PowerShell setup script so the forwarding rule uses the current address.

Browser works, but terminal traffic does not

A browser may have its own proxy configuration. Terminal applications will not automatically inherit it.

Set:

export ALL_PROXY="socks5h://VMNET8_HOST_IP:23322"

Some programs do not support SOCKS proxies directly and may require a wrapper such as proxychains4.

UDP does not work

Windows netsh interface portproxy forwards TCP only. It does not forward UDP. SOCKS-based applications that require UDP may therefore fail or fall back to a direct connection.

---

Security notes

• Bind the forwarding rule only to the VMnet8 address, not to 0.0.0.0.
• Restrict the firewall rule to LocalSubnet.
• Do not expose an unauthenticated SOCKS proxy to public or untrusted networks.
• Remove the forwarding and firewall rules when they are no longer needed.
• Treat the proxy exit IP as sensitive if it is tied to an account, subscription, or private endpoint.
• Verify DNS behavior with an appropriate leak-testing service before relying on the setup for privacy-sensitive work.

---

Important limitation

This setup makes a host-side SOCKS proxy reachable from the Ubuntu guest. It does not transparently route the entire Ubuntu operating system.

Only applications that explicitly use:

socks5h://VMNET8_HOST_IP:23322

will be proxied.