ESXi Local Account Created

[metadata]
creation_date = "2026/09/30"
integration = ["vsphere"]
maturity = "production"
updated_date = "2026/09/30"

[rule]
author = ["Elastic"]
description = """
Detects creation of a local ESXi account. A new account is a separate login that remains after the session that
created it. It has no rights until a role is assigned, and it is the first step toward a persistent login on the host.
"""
false_positives = [
    """
    Administrators create local accounts during onboarding or break-glass setup. Confirm the account name and whether
it was then granted the Admin role.
    """,
]
from = "now-9m"
index = ["logs-vsphere.log-*"]
language = "kuery"
license = "Elastic License v2"
name = "ESXi Local Account Created"
note = """## Triage and analysis

### Investigating ESXi Local Account Created

Hostd records Account <name> was created on host <hostname> when an account is added from the Host Client or API. The shell records esxcli system account add. The new account has no role until a later permission change.

#### Possible investigation steps

- Read the account name in message and the user field on the hostd event, which is the account that created it.
- Look for a following esxcli system permission set or an Admin role grant for the same account.
- Compare the account with the approved list for that host.

### False positive analysis

A documented joiner or break-glass account is commonly benign. An unknown account created by root over the Host Client, then granted Admin, deserves review.

### Response and remediation

- If the account was not approved, remove it with esxcli system account remove --id <name>.
- Preserve hostd.log and shell.log for the creating session.
"""
references = [
    "https://lolesxi-project.github.io/LOLESXi/#",
    "https://blogs.vmware.com/security/2022/10/esxi-targeting-ransomware-tactics-and-techniques-part-2.html",
    "https://detect.fyi/vmware-esxi-logging-detection-opportunities-4fb56411ec21",
]
setup = """## Setup

This rule requires ESXi host logs collected by the Elastic vSphere integration: https://www.elastic.co/docs/reference/integrations/vsphere
"""
risk_score = 47
rule_id = "dff0caa0-9d14-5e75-946b-677c38734e9b"
severity = "medium"
tags = [
    "Domain: Endpoint",
    "Data Source: VMware vSphere",
    "Use Case: Threat Detection",
    "Tactic: Persistence",
    "Resources: Investigation Guide",
    "Rule Type: Custom Query (KQL)",
    "Platform: VMware ESXi",
    "Threat: Ransomware",
]
timestamp_override = "event.ingested"
type = "query"

query = '''
data_stream.dataset:vsphere.log and event.module:vsphere and message:("esxcli system account add" or Account and "was created")
'''

[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1136"
name = "Create Account"
reference = "https://attack.mitre.org/techniques/T1136/"
[[rule.threat.technique.subtechnique]]
id = "T1136.001"
name = "Local Account"
reference = "https://attack.mitre.org/techniques/T1136/001/"

[rule.threat.tactic]
id = "TA0003"
name = "Persistence"
reference = "https://attack.mitre.org/tactics/TA0003/"

[rule.investigation_fields]
field_names = [
    "@timestamp",
    "message",
    "event.original",
    "host.hostname",
    "log.file.path",
]