ESXi Lockdown Mode Disabled

name: ESXi Lockdown Mode Disabled
id: 07c0d28a-9a9b-409f-8d4b-65355bd19ead
version: 5
creation_date: '2025-07-11'
modification_date: '2026-05-13'
author: Raven Tait, Splunk
status: production
type: TTP
description: This detection identifies when Lockdown Mode is disabled on an ESXi host, which can indicate that a threat actor is attempting to weaken host security controls. Disabling Lockdown Mode allows broader remote access via SSH or the host client and may precede further malicious actions such as data exfiltration, lateral movement, or VM tampering.
data_source:
    - VMWare ESXi Syslog
search: '`esxi_syslog` Message IN ("*lockdownmode.disabled*", "*Administrator access to the host has been enabled*") | rex field=_raw "Z (?<dest>[\w\.]+)\s" | stats min(_time) as firstTime max(_time) as lastTime count by dest Message | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `esxi_lockdown_mode_disabled_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.
finding:
    title: Lockdown Mode has been disabled on ESXi host $dest$.
    entity:
        field: dest
        type: system
        score: 50
analytic_story:
    - ESXi Post Compromise
    - Black Basta Ransomware
asset_type: Infrastructure
mitre_attack_id:
    - T1685
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: application
security_domain: endpoint