Permissions for Windows installation directory must conform to minimum requirements.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-40179	WN12-GE-000008	SV-52137r3_rule		Medium

Description
Changing the system's file and directory permissions allows the possibility of unauthorized and anonymous modification to the operating system and installed applications. The default permissions are adequate when the Security Option "Network access: Let everyone permissions apply to anonymous users" is set to "Disabled" (V-3377).

STIG	Date
Windows Server 2012/2012 R2 Domain Controller Security Technical Implementation Guide	2018-09-05

Details

Check Text ( C-46948r2_chk )
The default permissions are adequate when the Security Option "Network access: Let everyone permissions apply to anonymous users" is set to "Disabled" (V-3377). If the default ACLs are maintained and the referenced option is set to "Disabled", this is not a finding. Verify the default permissions for the Windows installation directory (usually C:\Windows). Nonprivileged groups such as Users or Authenticated Users must not have greater than Read & execute permissions except where noted as defaults. (Individual accounts must not be used to assign permissions.) Viewing in File Explorer: View the Properties of the folder. Select the "Security" tab, and the "Advanced" button. Default Permissions: \Windows Type - "Allow" for all Inherited from - "None" for all Principal - Access - Applies to TrustedInstaller - Full control - This folder and subfolders SYSTEM - Modify - This folder only SYSTEM - Full control - Subfolders and files only Administrators - Modify - This folder only Administrators - Full control - Subfolders and files only Users - Read & execute - This folder, subfolders and files CREATOR OWNER - Full control - Subfolders and files only ALL APPLICATION PACKAGES - Read & execute - This folder, subfolders and files Alternately, use Icacls: Open a Command prompt (admin). Enter icacls followed by the directory: icacls c:\windows The following results should be displayed: c:\windows NT SERVICE\TrustedInstaller:(F) NT SERVICE\TrustedInstaller:(CI)(IO)(F) NT AUTHORITY\SYSTEM:(M) NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F) BUILTIN\Administrators:(M) BUILTIN\Administrators:(OI)(CI)(IO)(F) BUILTIN\Users:(RX) BUILTIN\Users:(OI)(CI)(IO)(GR,GE) CREATOR OWNER:(OI)(CI)(IO)(F) APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(RX) APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE) Successfully processed 1 files; Failed processing 0 files

Check Text ( C-46948r2_chk )

The default permissions are adequate when the Security Option "Network access: Let everyone permissions apply to anonymous users" is set to "Disabled" (V-3377). If the default ACLs are maintained and the referenced option is set to "Disabled", this is not a finding.

Verify the default permissions for the Windows installation directory (usually C:\Windows). Nonprivileged groups such as Users or Authenticated Users must not have greater than Read & execute permissions except where noted as defaults. (Individual accounts must not be used to assign permissions.)

Viewing in File Explorer:
View the Properties of the folder.
Select the "Security" tab, and the "Advanced" button.

Default Permissions:
\Windows
Type - "Allow" for all
Inherited from - "None" for all

Principal - Access - Applies to

TrustedInstaller - Full control - This folder and subfolders
SYSTEM - Modify - This folder only
SYSTEM - Full control - Subfolders and files only
Administrators - Modify - This folder only
Administrators - Full control - Subfolders and files only
Users - Read & execute - This folder, subfolders and files
CREATOR OWNER - Full control - Subfolders and files only
ALL APPLICATION PACKAGES - Read & execute - This folder, subfolders and files

Alternately, use Icacls:

Open a Command prompt (admin).
Enter icacls followed by the directory:

icacls c:\windows

The following results should be displayed:

c:\windows
NT SERVICE\TrustedInstaller:(F)
NT SERVICE\TrustedInstaller:(CI)(IO)(F)
NT AUTHORITY\SYSTEM:(M)
NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F)
BUILTIN\Administrators:(M)
BUILTIN\Administrators:(OI)(CI)(IO)(F)
BUILTIN\Users:(RX)
BUILTIN\Users:(OI)(CI)(IO)(GR,GE)
CREATOR OWNER:(OI)(CI)(IO)(F)
APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(RX)
APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE)
Successfully processed 1 files; Failed processing 0 files

Fix Text (F-45163r1_fix)
Maintain the default file ACLs and configure the Security Option: "Network access: Let everyone permissions apply to anonymous users" to "Disabled" (V-3377). Default Permissions: Type - "Allow" for all Inherited from - "None" for all Principal - Access - Applies to TrustedInstaller - Full control - This folder and subfolders SYSTEM - Modify - This folder only SYSTEM - Full control - Subfolders and files only Administrators - Modify - This folder only Administrators - Full control - Subfolders and files only Users - Read & execute - This folder, subfolders and files CREATOR OWNER - Full control - Subfolders and files only ALL APPLICATION PACKAGES - Read & execute - This folder, subfolders and files

Fix Text (F-45163r1_fix)

Maintain the default file ACLs and configure the Security Option: "Network access: Let everyone permissions apply to anonymous users" to "Disabled" (V-3377).

Default Permissions:
Type - "Allow" for all
Inherited from - "None" for all

Principal - Access - Applies to

TrustedInstaller - Full control - This folder and subfolders
SYSTEM - Modify - This folder only
SYSTEM - Full control - Subfolders and files only
Administrators - Modify - This folder only
Administrators - Full control - Subfolders and files only
Users - Read & execute - This folder, subfolders and files
CREATOR OWNER - Full control - Subfolders and files only
ALL APPLICATION PACKAGES - Read & execute - This folder, subfolders and files