Title

Anonymous shares are not restricted. (Cat I impact)

Discussion

This is a Category 1 finding because it allows anonymous logon users (null session connections) to list all account names and enumerate all shared resources, thus providing a map of potential points to attack the system. By default, Windows allows anonymous users to list account names and enumerate share names.

Check Content

Analyze the system using the Security Configuration and Analysis snap-in. Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. If the value for “Network access: Do not allow anonymous enumeration of SAM accounts” is not set to “Enabled”, then this is a finding. If the value for “Network access: Do not allow anonymous enumeration of SAM accounts and shares” is not set to “Enabled”, then this is a finding. The policies referenced configure the following registry values: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Control\Lsa\ Value Name: RestrictAnonymousSAM (Sam accounts) And Value Name: RestrictAnonymous (Sam accounts and shares) Value Type: REG_DWORD Value: 1 Documentable Explanation: If the required settings cannot be used to allow for proper operation in a mixed Windows environment, then this should be documented with the IAO.

Fix Text

Configure the policy values for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> “Network access: Do not allow anonymous enumeration of SAM accounts” and “Network access: Do not allow anonymous enumeration of SAM accounts and shares” to “Enabled".

Additional Identifiers

Rule ID: SV-1093r1_rule

Vulnerability ID: V-1093

Group Title: Anonymous shares are not restricted

Expert Comments

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