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Detection rules › Kusto

VMware ESXi - Shared or stolen root account

Status
available
Severity
high
Time window
15m
Group by
SrcIpAddr
Source
github.com/Azure/Azure-Sentinel

'Detects when shared or stolen root account.'

MITRE ATT&CK coverage

TacticTechniques
Initial Access
Privilege Escalation

Rule body

id: 9c496d6c-42a3-4896-9b6c-00254386928f
name: VMware ESXi - Shared or stolen root account
description: |
  'Detects when shared or stolen root account.'
severity: High
status: Available
requiredDataConnectors:
  - connectorId: SyslogAma
    datatypes:
      - Syslog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 1
tactics:
  - InitialAccess
  - PrivilegeEscalation
relevantTechniques:
  - T1078
query: |
  VMwareESXi
  | where SyslogMessage has_all ('UserLoginSessionEvent', 'root', 'logged in')
  | extend SrcIpAddr = extract(@'root@(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})', 1, SyslogMessage)
  | summarize count() by SrcIpAddr, bin(TimeGenerated, 15m)
  | where count_ > 1
  | extend IPCustomEntity = SrcIpAddr
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPCustomEntity
version: 1.0.3
kind: Scheduled

Stages and Predicates

Stage 1: source

VMwareESXi

Stage 2: where

| where SyslogMessage has_all ('UserLoginSessionEvent', 'root', 'logged in')

Stage 3: extend

| extend SrcIpAddr = extract(@'root@(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})', 1, SyslogMessage)

Stage 4: summarize

| summarize count() by SrcIpAddr, bin(TimeGenerated, 15m)

Stage 5: where

| where count_ > 1

Stage 6: extend

| extend IPCustomEntity = SrcIpAddr

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
SyslogMessagematch
  • UserLoginSessionEvent transforms: term
  • logged in transforms: term
  • root transforms: term
field:"SyslogMessage" kind:match
count_gt
  • 1
field:"count_" kind:gt value:"1"

Output fields

These fields are emitted when the rule matches.

FieldSource
SrcIpAddrsummarize
IPCustomEntityextend