ESXi VM List 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: f67cdcb6670752cdfc18cf1c4639def409fdefd344b36d82ecea0a391b27d617

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 VM List Discovery Via ESXCLI
id: 5f1573a7-363b-4114-9208-ad7a61de46eb
status: test
description: Detects execution of the "esxcli" command with the "vm" flag in order to retrieve information about the installed VMs.
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_vm.html
    - https://www.secuinfra.com/en/techtalk/hide-your-hypervisor-analysis-of-esxiargs-ransomware/
    - https://www.trendmicro.com/en_us/research/22/e/new-linux-based-ransomware-cheerscrypt-targets-exsi-devices.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:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'vm process'
        CommandLine|endswith: ' list'
    condition: 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_vm.html
• https://www.secuinfra.com/en/techtalk/hide-your-hypervisor-analysis-of-esxiargs-ransomware/
• https://www.trendmicro.com/en_us/research/22/e/new-linux-based-ransomware-cheerscrypt-targets-exsi-devices.html