Linux Process Creation: ESXi User Account Added via esxcli system account add

Alerts when esxcli is used to run an ESXi system account add command, indicating user account creation.

FreeReviewedSigma · Medium · v3
Product
linux
Category
process_creation
Author
Cedric Maurugeon (SigmaHQ), DRL 1.1
Published
2023-08-22
Updated
2026-07-31
title: "Linux Process Creation: ESXi User Account Added via esxcli system account add"
id: 9b53cfc7-f866-43a9-9bc4-d02ee044d8b0
status: test
description: This rule matches process executions where the command line invokes esxcli to add an ESXi system user account ("system account add"). Account creation on ESXi can enable persistence and unauthorized access, making this activity high-signal for investigation. It relies on process creation telemetry, specifically the executable path ending with /esxcli and command-line arguments containing the relevant esxcli subcommands.
references:
  - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_esxcli_user_account_creation.yml
author: Cedric Maurugeon, Huntrule Team
date: 2023-08-22
tags:
  - attack.persistence
  - attack.execution
  - attack.t1136
  - attack.t1059.012
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith: /esxcli
    CommandLine|contains|all:
      - "system "
      - "account "
      - "add "
  condition: selection
falsepositives:
  - Legitimate administration activities
level: medium
license: DRL-1.1
related:
  - id: b28e4eb3-8bbc-4f0c-819f-edfe8e2f25db
    type: derived