atomic-red-team/atomics/T1139/T1139.md

T1139 - Bash History

Description from ATT&CK

Bash keeps track of the commands users type on the command-line with the "history" utility. Once a user logs out, the history is flushed to the user’s .bash_history file. For each user, this file resides at the same location: ~/.bash_history. Typically, this file keeps track of the user’s last 500 commands. Users often type usernames and passwords on the command-line as parameters to programs, which then get saved to this file when they log out. Attackers can abuse this by looking through the file for potential credentials. (Citation: External to DA, the OS X Way)

Detection: Monitoring when the user's .bash_history is read can help alert to suspicious activity. While users do typically rely on their history of commands, they often access this history through other utilities like "history" instead of commands like cat ~/.bash_history.

Platforms: Linux, macOS

Data Sources: File monitoring, Process monitoring, Process command-line parameters

Permissions Required: User

Atomic Tests

• Atomic Test #1 - xxxx

Atomic Test #1 - xxxx

xxxx

Supported Platforms: Linux, macOS

Inputs

Name	Description	Type	Default Value
bash_history_filename	Path of the bash history file to capture	Path	~/.bash_history
bash_history_grep_args	grep arguments that filter out specific commands we want to capture	Path	-e '-p ' -e 'pass' -e 'ssh'
output_file	Path where captured results will be placed	Path	~/loot.txt

Run it with sh!

cat #{bash_history_filename} | grep #{bash_history_grep_args} > #{output_file}