Vulnerability Discussion

The server message block (SMB) protocol provides the basis for many network operations. If this policy is enabled, the SMB client will request packet signing when communicating with an SMB server that is enabled or required to perform SMB packet signing.

Satisfies: SRG-OS-000423-GPOS-00187, SRG-OS-000424-GPOS-00188

Check

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

Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters\

Value Name: EnableSecuritySignature

Value Type: REG_DWORD
Value: 0x00000001 (1)

Fix

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> Microsoft network client: Digitally sign communications (if server agrees) to "Enabled".