Contains data describing the Access Control List (ACL) of the principals that can access instances of this class. This ACL is only used by applications that do not call CoInitializeSecurity.
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\APPID\
{AppID_value}\AccessPermission = ACL
This named-value is a REG_BINARY. It contains data describing the Access Control List (ACL) of the principals that can access instances of this class. Upon receiving a request to connect to an existing object of this class, the ACL is checked by the application being called while impersonating the caller. If the access-check fails the connection is disallowed. If this named-value does not exist, the machine-wide DefaultAccessPermission ACL is tested in an identical manner (see above) as a default to determine if the connection is to be allowed.
DefaultAccessPermission, Security in COM