Modification of Environment Variable via Launchctl

Elastic Stack Serverless Security

Identifies modifications to an environment variable using the built-in launchctl command. Adversaries may execute their own malicious payloads by hijacking certain environment variables to load arbitrary libraries or bypass certain restrictions.

Rule type: query

Rule indices:

auditbeat-*
logs-endpoint.events.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

https://github.com/rapid7/metasploit-framework/blob/master//modules/post/osx/escalate/tccbypass.rb

Tags:

Elastic
Host
macOS
Threat Detection
Defense Evasion

Version: 101

Rule authors:

Elastic

Rule license: Elastic License v2

Rule query

		event.category:process and event.type:start and
  process.name:launchctl and
  process.args:(setenv and not (JAVA*_HOME or
                                RUNTIME_JAVA_HOME or
                                DBUS_LAUNCHD_SESSION_BUS_SOCKET or
                                ANT_HOME or
                                LG_WEBOS_TV_SDK_HOME or
                                WEBOS_CLI_TV or
                                EDEN_ENV)
                ) and
  not process.parent.executable:("/Applications/NoMachine.app/Contents/Frameworks/bin/nxserver.bin" or
                                 "/usr/local/bin/kr" or
                                 "/Applications/NoMachine.app/Contents/Frameworks/bin/nxserver.bin" or
                                 "/Applications/IntelliJ IDEA CE.app/Contents/jbr/Contents/Home/lib/jspawnhelper") and
  not process.args : "*.vmoptions"

	

Framework: MITRE ATT&CKTM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Hijack Execution Flow
- ID: T1574
- Reference URL: https://attack.mitre.org/techniques/T1574/
Sub-technique:
- Name: Path Interception by PATH Environment Variable
- ID: T1574.007
- Reference URL: https://attack.mitre.org/techniques/T1574/007/