Persistence via Login or Logout Hookedit

Identifies use of the defaults command to install a login or logoff hook in MacOS. An adversary may abuse this capability to establish persistence in an environment by inserting code to be executed at login or logout.

Rule type: eql

Rule indices:

  • auditbeat-*
  • logs-endpoint.events.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Host
  • macOS
  • Threat Detection
  • Persistence

Version: 5

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guideedit

## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.

Rule queryedit

process where event.type == "start" and
 process.name == "defaults" and process.args == "write" and process.args in ("LoginHook", "LogoutHook") and
 not process.args :
       (
         "Support/JAMF/ManagementFrameworkScripts/logouthook.sh",
         "Support/JAMF/ManagementFrameworkScripts/loginhook.sh",
         "/Library/Application Support/JAMF/ManagementFrameworkScripts/logouthook.sh",
         "/Library/Application Support/JAMF/ManagementFrameworkScripts/loginhook.sh"
       )

Framework: MITRE ATT&CKTM