Title

Permissions for system files and directories must conform to minimum requirements. (Cat II impact)

Discussion

Changing the system's file and directory permissions allows the possibility of unauthorized and anonymous modification to the operating system and installed applications.

Check Content

The default ACL settings 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 sample directories below. Non-privileged 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 Windows Explorer: Right click on the directory and select "Properties". Select the "Security" tab, and the "Advanced" button. C:\ Type - "Allow" for all Inherited from - "<not inherited>" for all Name - Permission - Apply to Administrators - Full control - This folder, subfolders and files SYSTEM - Full control - This folder, subfolders and files Users - Read & execute - This folder, subfolders and files Authenticated Users - Special - Subfolders and files only (Special = all permissions except Full Control, Delete subfolders and files, Change permissions, and Take ownership when viewing permission details.) Authenticated Users - Create folders / append data - This folder only The Program Files, Program Files (x86), and Windows directories have the following default permissions: Type - "Allow" for all Inherited from - "<not inherited>" for all Name - Permission - Apply to TrustedInstaller - Special - This folder and subfolders (Special = Full control when viewing permission details.) SYSTEM - Special - This folder only (Special = all permissions except Full Control, Delete subfolders and files, Change permissions, and Take ownership when viewing permission details.) SYSTEM - Special - Subfolders and files only (Special = Full control when viewing permission details.) Administrators - Special - This folder only (Special = all permissions except Full Control, Delete subfolders and files, Change permissions, and Take ownership when viewing permission details.) Administrators - Special - Subfolders and files only (Special = Full control when viewing permission details.) Users - Read & execute - This folder, subfolders and files CREATOR OWNER - Special - Subfolders and files only (Special = Full control when viewing permission details.) Alternately use Icacls. In a Command prompt (admin) Enter icacls followed by the directory. icacls c:\ icacls "c:\program files" of "c:\program files (x86)" icacls c:\windows The following results will be displayed as each is entered: c:\ BUILTIN\Administrators:(F) BUILTIN\Administrators:(OI)(CI)(IO)(F) NT AUTHORITY\SYSTEM:(F) NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F) BUILTIN\Users:(OI)(CI)(RX) NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(M) NT AUTHORITY\Authenticated Users:(AD) Mandatory Label\High Mandatory Level:(OI)(NP)(IO)(NW) Successfully processed 1 files; Failed processing 0 files c:\program files, c:\program files (x86), and 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) Successfully processed 1 files; Failed processing 0 files If a permission setting prevents a site's applications from performing properly, settings must only be changed to the minimum necessary for the application to function. Each exception must be documented with the ISSO.

Fix Text

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

Additional Identifiers

Rule ID:

Vulnerability ID: V-1130

Group Title:

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.