Handling guidance for agencies on information about HVAs can be found on MAX 14
As noted throughout the document, the HVA initiative relies on the identification and prioritization of HVAs for testing and assessment based on numerous factors including the type and amount of information, criticality to mission essential functions, and adversary Tactics Techniques, and Procedures (TTPs). The identification and prioritization of these systems is critical to conducting assessments efficiently, but the results of these efforts are also an attractive target to anyone with malicious intent. To ensure the access needed to perform their appropriate functions while protecting the information about these critical systems, both agencies and independent third party assessors are expected to follow the handling guidance, except for classified national security information which should follow established guidance.
If a specific process or information is not listed, then it does not have unique handling or protection guidance in terms of being related to an HVA. However, any information submitted by outside agencies that is covered by separate classification guidance should retain the appropriate level of classification.