Types or members that are marked with the System.Security.SecuritySafeCriticalAttribute attribute can be accessed by partially trusted types and members. These partially trusted types and members can be within any assembly that is marked with the System.Security.SecurityTransparentAttribute or System.Security.AllowPartiallyTrustedCallersAttribute (APTCA) attribute, or they are partially trusted for other reasons, such as being loaded into partial trust. Code that is marked with the System.Security.SecuritySafeCriticalAttribute must be subject to a rigorous security audit to ensure that it can be used safely in a secure execution environment. Security-safe-critical code must validate the permissions of callers to determine whether they have authority to access protected resources used by the code.