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T0804 Block Reporting Message

Adversaries may block or prevent a reporting message from reaching its intended target. In control systems, reporting messages contain telemetry data (e.g., I/O values) pertaining to the current state of equipment and the industrial process. By blocking these reporting messages, an adversary can potentially hide their actions from an operator.

Blocking reporting messages in control systems that manage physical processes may contribute to system impact, causing inhibition of a response function. A control system may not be able to respond in a proper or timely manner to an event, such as a dangerous fault, if its corresponding reporting message is blocked. 1 2

Item Value
ID T0804
Sub-techniques
Tactics TA0107
Platforms None
Version 1.0
Created 21 May 2020
Last Modified 16 April 2025

Procedure Examples

ID Name Description
C0028 2015 Ukraine Electric Power Attack During the 2015 Ukraine Electric Power Attack, Sandworm Team blocked reporting messages by using malicious firmware to render serial-to-ethernet converters inoperable. 4
S0604 Industroyer Industroyer uses the first COM port from the configuration file for the communication and the other two COM ports are opened to prevent other processes accessing them. This may block processes or operators from getting reporting messages from a device. 3

Mitigations

ID Mitigation Description
M0807 Network Allowlists Utilize network allowlists to restrict unnecessary connections to network devices (e.g., comm servers, serial to ethernet converters) and services, especially in cases when devices have limits on the number of simultaneous sessions they support.
M0810 Out-of-Band Communications Channel Provide an alternative method for sending critical report messages to operators, this could include using radio/cell communication to obtain messages from field technicians that can locally obtain telemetry and status data.
M0814 Static Network Configuration Unauthorized connections can be prevented by statically defining the hosts and ports used for automation protocol connections.

References

  1. Bonnie Zhu, Anthony Joseph, Shankar Sastry 2011 A Taxonomy of Cyber Attacks on SCADA Systems Retrieved. 2018/01/12  ↩

  2. Electricity Information Sharing and Analysis Center; SANS Industrial Control Systems 2016, March 18 Analysis of the Cyber Attack on the Ukranian Power Grid: Defense Use Case Retrieved. 2018/03/27  ↩

  3. Anton Cherepanov, ESET 2017, June 12 Win32/Industroyer: A new threat for industrial control systems Retrieved. 2017/09/15  ↩

  4. Electricity Information Sharing and Analysis Center; SANS Industrial Control Systems. (2016, March 18). Analysis of the Cyber Attack on the Ukranian Power Grid: Defense Use Case. Retrieved March 27, 2018. ↩