Information
The NULL cipher does not provide data confidentiality or integrity. It is recommended that the NULL cipher be disabled.
By disabling the NULL cipher, there is a better chance of maintaining data confidentiality and integrity.
Solution
To disable the NULL cipher, ensure the following key is absent. If the key is present, ensure it is set to 0.
HKLM System\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\NULL\Enabled