Level 5: Invariant Behaviors / Core to Technique

Description: Observables associated with invariant behaviors or behavioral chokepoints that all implementations of a technique or sub-technique must exhibit.

Level 5 observables represent fundamental behaviors that cannot be avoided without abandoning the technique altogether. They are shared across the known implementation space and therefore provide the most robust detection opportunities in the Summiting the Pyramid model. An invariant behavior is not simply an observable that appears frequently. It is a behavior that is fundamentally required for accomplishing the technique.

Why are these observables placed at Level 5?

Level 5 observables are behavioral chokepoints: points where different implementations converge on an interaction that is fundamental to achieving the technique. Because every implementation must exhibit the behavior, the adversary cannot evade a Level 5 detection by changing tools, configuration, or implementation strategy while still performing the same technique. To evade the detection, the adversary must instead switch to an entirely different ATT&CK technique. Identifying invariant behaviors therefore provides the most robust detection opportunities in the Summiting the Pyramid model.

Observables

The examples below illustrate invariant behaviors that occur across implementations of a technique.

Technique / Sub-Technique

Observable

Invariant Behavior

Scheduled Tasks (T1053)

TargetObject = HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Schedule\\TaskCache\\Tree or HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Schedule\\TaskCache\\Tasks

Creation of a scheduled task results in the Task Scheduler maintaining corresponding Registry data regardless of the implementation used to create the task.

OS Credential Dumping: DCSync (T1003.006)

RPC endpoint/interface drsuapi with operations such as DRSReplicaSync or DRSGetNCChanges

These operations represent the directory replication activity required by DCSync implementations using this mechanism.

References [1] [2] [3] [4]