splunk_escuTTP

ESXi Bulk VM Termination

This detection identifies when all virtual machines on an ESXi host are abruptly terminated, which may indicate malicious activity such as a deliberate denial-of-service, ransomware staging, or an attempt to destroy critical workloads.

MITRE ATT&CK

T1673 T1529 T1499

Detection Query

`esxi_syslog` | rex field=_raw "\s\[(?<user>[^\]]+)\]:\s(?<shell_command>.+)$" | rex field=_raw "Z (?<dest>[\w\.]+)\s.*:\s(?<esxicli_Command>esxcli\s.+)" | eval command=mvappend(esxicli_Command, shell_Command) | where isnotnull(command) | search (command="pkill -9 vmx-*") OR ( command="*esxcli*" AND command="*--format-param*" AND command="*vm process list*" AND command="*awk*" AND command="*esxcli vm process kill*") | stats min(_time) as firstTime max(_time) as lastTime values(_time) as timeStamp values(command) as commands values(user) as user by dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `esxi_bulk_vm_termination_filter`

Author

Raven Tait, Splunk

Created

2026-03-10

Data Sources

VMWare ESXi Syslog

Tags

ESXi Post CompromiseBlack Basta Ransomware

Raw Content

name: ESXi Bulk VM Termination
id: cfe094b4-0737-4a33-9d63-e0562ce2b883
version: 2
date: '2026-03-10'
author: Raven Tait, Splunk
status: production
type: TTP
description: This detection identifies when all virtual machines on an ESXi host are abruptly terminated, which may indicate malicious activity such as a deliberate denial-of-service, ransomware staging, or an attempt to destroy critical workloads.
data_source:
    - VMWare ESXi Syslog
search: '`esxi_syslog` | rex field=_raw "\s\[(?<user>[^\]]+)\]:\s(?<shell_command>.+)$" | rex field=_raw "Z (?<dest>[\w\.]+)\s.*:\s(?<esxicli_Command>esxcli\s.+)" | eval command=mvappend(esxicli_Command, shell_Command) | where isnotnull(command) | search (command="pkill -9 vmx-*") OR ( command="*esxcli*" AND command="*--format-param*" AND command="*vm process list*" AND command="*awk*" AND command="*esxcli vm process kill*") | stats min(_time) as firstTime max(_time) as lastTime values(_time) as timeStamp values(command) as commands values(user) as user by dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `esxi_bulk_vm_termination_filter`'
how_to_implement: This is based on syslog data generated by VMware ESXi hosts. To implement this search, you must configure your ESXi systems to forward syslog output to your Splunk deployment. These logs must be ingested with the appropriate Splunk Technology Add-on for VMware ESXi Logs, which provides field extractions and CIM compatibility.
known_false_positives: Limited false positives in most environments, however tune as needed.
drilldown_searches:
    - name: View the detection results for - "$dest$"
      search: '%original_detection_search% | search  dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") starthoursago=168  | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
rba:
    message: Bulk VM termination activity on ESXi host $dest$.
    risk_objects:
        - field: dest
          type: system
          score: 50
    threat_objects: []
tags:
    analytic_story:
        - ESXi Post Compromise
        - Black Basta Ransomware
    asset_type: Infrastructure
    mitre_attack_id:
        - T1673
        - T1529
        - T1499
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1529/esxi_bulk_vm_termination/esxi_bulk_vm_termination.log
          source: vmware:esxlog
          sourcetype: vmw-syslog