ESXi System Information Discovery Via ESXCLI — Sigma Rule

Rule metadata and linked tags

Author: Cedric Maurugeon. Source status: test; severity: medium. Source dates: 2023-09-04 / not supplied.

{
  "category": "process_creation",
  "product": "linux"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 0070047c7390551f7d60ae1a42328fd2331dd4bb976cda26a7c61667703a3b20

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: ESXi System Information Discovery Via ESXCLI
id: e80273e1-9faf-40bc-bd85-dbaff104c4e9
status: test
description: Detects execution of the "esxcli" command with the "system" flag in order to retrieve information about the different component of the system. Such as accounts, modules, NTP, etc.
references:
    - https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
author: Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection_img:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'system'
    selection_cli:
        CommandLine|contains:
            - ' get'
            - ' list'
    condition: all of selection_*
falsepositives:
    - Legitimate administration activities
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate administration activities

Source references

• https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
• https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html