Windows Server 2025 unencrypted passwords must not be sent to third-party Server Message Block (SMB) servers.

Some non-Microsoft SMB servers only support unencrypted (plain-text) password authentication. Sending plain-text passwords across the network when authenticating to an SMB server reduces the overall security of the environment. Check with the vendor of the SMB server to determine if there is a way to support encrypted password authentication.

If the following registry value does not exist or is not configured as specified, this is a finding:

Registry HiveHKEY_LOCAL_MACHINE Registry Path\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters\

Value NameEnablePlainTextPassword

Value TypeREG_DWORD Value0x00000000 (0)

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> Microsoft Network Client: Send unencrypted password to third-party SMB servers to "Disabled".