Adversaries may spoof reporting messages in control system environments for evasion and to impair process control. In control systems, reporting messages contain telemetry data (e.g., I/O values) pertaining to the current state of equipment and the industrial process. Reporting messages are important for monitoring the normal operation of a system or identifying important events such as deviations from expected values. The adversary can Spoof Reporting Messages that state that the process is operating normally, as a form of evasion. The adversary could also make the defenders and operators think that other errors are occurring.”]
Source: https://collaborate.mitre.org/attackics/index.php/Technique/T0856