Attempt to Mount SMB Share via Command Line

Identifies the execution of macOS built-in commands to mount a Server Message Block (SMB) network share. Adversaries may use valid accounts to interact with a remote network share using SMB.

Rule type: eql

Rule indices:

auditbeat-*
logs-endpoint.events.*

Severity: low

Risk score: 21

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
Lateral Movement

Version: 5

Rule authors:

Elastic

Rule license: Elastic License v2

Investigation guide

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## Setup

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 query

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process where event.type in ("start", "process_started") and
  (
    process.name : "mount_smbfs" or
    (process.name : "open" and process.args : "smb://*") or
    (process.name : "mount" and process.args : "smbfs") or
    (process.name : "osascript" and process.command_line : "osascript*mount volume*smb://*")
  ) and
  not process.parent.executable : "/Applications/Google Drive.app/Contents/MacOS/Google Drive"

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Lateral Movement
- ID: TA0008
- Reference URL: https://attack.mitre.org/tactics/TA0008/
Technique:
- Name: Remote Services
- ID: T1021
- Reference URL: https://attack.mitre.org/techniques/T1021/
Sub-technique:
- Name: SMB/Windows Admin Shares
- ID: T1021.002
- Reference URL: https://attack.mitre.org/techniques/T1021/002/

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