Windows 11 must not have portproxy enabled or in use.

Documentable No

Rule ID SV-257592r991589_rule

CCI References

CCI-000381

Discussion

Having portproxy enabled or configured in Windows 10 could allow a man-in-the-middle attack.

Check Procedure

Check the registry key for existence of proxied ports:
HKLM\SYSTEM\CurrentControlSet\Services\PortProxy\.

If the key contains v4tov4\tcp\ or is populated v4tov4\tcp\, this is a finding.

Run "netsh interface portproxy show all".

If the command displays any results, this is a finding.

Fix Action

Contact the Administrator to run "netsh interface portproxy delete" with elevation. Remove any enabled portproxies that may be configured.