Impair Defenses: Indicator Blocking

An adversary may attempt to block indicators or events typically captured by sensors from being gathered and analyzed. This could include maliciously redirecting [1] or even disabling host-based sensors, such as Event Tracing for Windows (ETW),[2] by tampering settings that control the collection and flow of event telemetry. [3] These settings may be stored on the system in configuration files and/or in the Registry as well as being accessible via administrative utilities such as PowerShell or Windows Management Instrumentation.

ETW interruption can be achieved multiple ways, however most directly by defining conditions using the PowerShell Set-EtwTraceProvider cmdlet or by interfacing directly with the Registry to make alterations.

In the case of network-based reporting of indicators, an adversary may block traffic associated with reporting to prevent central analysis. This may be accomplished by many means, such as stopping a local process responsible for forwarding telemetry and/or creating a host-based firewall rule to block traffic to specific hosts responsible for aggregating events, such as security information and event management (SIEM) products.

ID: T1562.006
Sub-technique of:  T1562
Tactic: Defense Evasion
Platforms: Linux, Windows, macOS
Defense Bypassed: Anti-virus, Host intrusion prevention systems
Contributors: Rob Smith
Version: 1.0
Created: 19 March 2020
Last Modified: 13 January 2021

Procedure Examples

ID Name Description
S0377 Ebury

Ebury can hook logging functions so that nothing from the backdoor gets sent to the logging facility.[4]

S0697 HermeticWiper

HermeticWiper has the ability to set the HKLM:\SYSTEM\\CurrentControlSet\\Control\\CrashControl\CrashDumpEnabled Registry key to 0 in order to disable crash dumps.[5][6][7]

S0579 Waterbear

Waterbear can hook the ZwOpenProcess and GetExtendedTcpTable APIs called by the process of a security product to hide PIDs and TCP records from detection.[8]


ID Mitigation Description
M1022 Restrict File and Directory Permissions

Ensure event tracers/forwarders [9], firewall policies, and other associated mechanisms are secured with appropriate permissions and access controls.

M1054 Software Configuration

Consider automatically relaunching forwarding mechanisms at recurring intervals (ex: temporal, on-logon, etc.) as well as applying appropriate change management to firewall rules and other related system configurations.

M1018 User Account Management

Ensure event tracers/forwarders [9], firewall policies, and other associated mechanisms are secured with appropriate permissions and access controls and cannot be manipulated by user accounts.


ID Data Source Data Component
DS0017 Command Command Execution
DS0013 Sensor Health Host Status
DS0024 Windows Registry Windows Registry Key Modification

Detect lack of reported activity from a host sensor. Different methods of blocking may cause different disruptions in reporting. Systems may suddenly stop reporting all data or only certain kinds of data.

Depending on the types of host information collected, an analyst may be able to detect the event that triggered a process to stop or connection to be blocked. For example, Sysmon will log when its configuration state has changed (Event ID 16) and Windows Management Instrumentation (WMI) may be used to subscribe ETW providers that log any provider removal from a specific trace session. [3] To detect changes in ETW you can also monitor the registry key which contains configurations for all ETW event providers: HKLM\SYSTEM\CurrentControlSet\Control\WMI\Autologger\AUTOLOGGER_NAME{{PROVIDER_GUID}}