Bash Shell Profile Modification
editBash Shell Profile Modification
editBoth ~/.bash_profile and ~/.bashrc are files containing shell commands that are run when Bash is invoked. These files are executed in a user’s context, either interactively or non-interactively, when a user logs in so that their environment is set correctly. Adversaries may abuse this to establish persistence by executing malicious content triggered by a user’s shell.
Rule type: query
Rule indices:
- logs-endpoint.events.*
- auditbeat-*
Severity: medium
Risk score: 47
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- macOS
- Linux
- Threat Detection
- Persistence
Version: 1
Added (Elastic Stack release): 7.12.0
Rule authors: Elastic
Rule license: Elastic License v2
Potential false positives
editChanges to the Shell Profile tend to be noisy, a tuning per your environment will be required.
Rule query
editevent.category:file and event.type:change and process.name:(* and not (sudo or vim or zsh or env or nano or bash or Terminal or xpcproxy or login or cat or cp or launchctl or java)) and not process.executable:(/Applications/* or /private/var/folders/* or /usr/local/*) and file.path:(/private/etc/rc.local or /etc/rc.local or /home/*/.profile or /home/*/.profile1 or /home/*/.bash_profile or /home/*/.bash_profile1 or /home/*/.bashrc or /Users/*/.bash_profile or /Users/*/.zshenv)
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Event Triggered Execution
- ID: T1546
- Reference URL: https://attack.mitre.org/techniques/T1546/