T1148.md

T1148 - HISTCONTROL

Description from ATT&CK

The HISTCONTROL environment variable keeps track of what should be saved by the history command and eventually into the ~/.bash_history file when a user logs out. This setting can be configured to ignore commands that start with a space by simply setting it to "ignorespace". HISTCONTROL can also be set to ignore duplicate commands by setting it to "ignoredups". In some Linux systems, this is set by default to "ignoreboth" which covers both of the previous examples. This means that “ ls” will not be saved, but “ls” would be saved by history. HISTCONTROL does not exist by default on macOS, but can be set by the user and will be respected. Adversaries can use this to operate without leaving traces by simply prepending a space to all of their terminal commands.

Atomic Tests

• Atomic Test #1 - Disable history collection

• Atomic Test #2 - Mac HISTCONTROL

Atomic Test #1 - Disable history collection

Disables history collection in shells

Supported Platforms: Linux, macOS

Inputs:

Name	Description	Type	Default Value
evil_command	Command to run after shell history collection is disabled	String	whoami

Attack Commands: Run with sh!

export HISTCONTROL=ignoreboth
ls #{evil_command}

Atomic Test #2 - Mac HISTCONTROL

Supported Platforms: macOS, Linux

Run it with these steps! 1. export HISTCONTROL=ignoreboth

2. echo export "HISTCONTROL=ignoreboth" >> ~/.bash_profile
3. ls
4. whoami > recon.txt