Impair Defenses: Impair Command History Logging

Created the Tuesday 07 February 2023. Updated 2 months, 3 weeks ago.

Adversaries may impair command history logging to hide commands they run on a compromised system. Various command interpreters keep track of the commands users type in their terminal so that users can retrace what they've done.

The PSReadLine module tracks commands used in all PowerShell sessions and writes them to a file ($env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ConsoleHost_history.txt by default).

Adversaries may change where these logs are saved using Set-PSReadLineOption -HistorySavePath {File Path}.

This will cause ConsoleHost_history.txt to stop receiving logs. Additionally, it is possible to turn off logging to this file using the PowerShell command Set-PSReadlineOption -HistorySaveStyle SaveNothing.

Adversaries may also leverage a Network Device CLI on network devices to disable historical command logging (e.g. no logging).

An adversary can manipulate command history logging in Bash on a Linux system by exploiting the HISTCONTROL environment variable, which determines how commands are recorded in the history file. By setting this variable to specific values, such as ignoreboth or ignorespace, any command that starts with a space will not be logged in the history file. This technique allows the adversary to conceal potentially malicious commands from future review:

export HISTCONTROL=ignorespace
whoami
id
cat /etc/passwd

Technique Identifier

T1562.003

Technique Tags

Defense Evasion PSReadLine ConsoleHost_history.txt $env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ Set-PSReadLineOption -HistorySavePath {File Path} Set-PSReadlineOption -HistorySaveStyle SaveNothing Network Device CLI APT38 disable logging disable historical command logging

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Impair Defenses: Impair Command History Logging, Sub-technique T1562.003 - Enterprise | MITRE ATT&CK®