Mandatory Integrity Control mechanism is in addition toDiscretionary Access Control and evaluates access before Access Control checks against an object's Discretionary Access Control List (DACL) are evaluated.
Mandatory Integrity Control uses integrity levels and Mandatory Access Control policy to determine access. Security Principal Objects and Securable objects are assigned Integrity Levels that determine their level of protection or access.
For example, a principal with a low Integrity Level cannot write to an object with a medium Integrity Level, even if that object's Discretionary Access Control List (DACL) allows write access to the Security Principal Objects.
The values defined for this access mask are
Every MSFT Access Token also specifies a mandatory policy that is set by the Local Security Authority (LSA) when the MSFT Access Token is created. This Access Control Policy is specified by a TOKEN_MANDATORY_POLICY structure associated with the MSFT Access Token. This structure can be queried by calling the GetTokenInformation function with the value of the TokenInformationClass parameter set to TokenMandatoryPolicy.