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

ATT&CK techniques

Execution → Persistence

Recon
Resource Dev
Initial Access
Execution
- T1059Command and Scripting Interpreter
Persistence
- T1136Create Account
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

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.

Reporting behind it

Related detections9 linkedT1059 — drag to rearrange

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

Pivot detection · T1059 · 9 related

Changelog

v3
Candidate ingested via manual entry.2026-07-31
v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

esxi-user-account-creation-via-esxcli-command-execution-b28e4eb3

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

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