Detection rules › Kusto

ApexOne - Possible exploit or execute operation

Status
available
Severity
high
Time window
1h
Source
github.com/Azure/Azure-Sentinel

'Detects possible exploit or execute operation.'

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1546 Event Triggered Execution
Privilege EscalationT1546 Event Triggered Execution

Rule body kusto

id: e289d762-6cc2-11ec-90d6-0242ac120003
name: ApexOne - Possible exploit or execute operation
description: |
  'Detects possible exploit or execute operation.'
severity: High
status: Available
requiredDataConnectors:
  - connectorId: CefAma
    dataTypes:
      - CommonSecurityLog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - PrivilegeEscalation
  - Persistence
relevantTechniques:
  - T1546
query: |
  TMApexOneEvent
  | where EventMessage has "Behavior Monitoring"
  | extend DeviceCustomNumber3 = coalesce(column_ifexists("FieldDeviceCustomNumber3", long(null)),DeviceCustomNumber3)
  | where Event_Type == 2048 or DeviceCustomNumber3 == 403 or DeviceCustomNumber3 == 601
  | extend IPCustomEntity = SrcIpAddr, AccountCustomEntity = DstUserName
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPCustomEntity
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: AccountCustomEntity
version: 1.0.5
kind: Scheduled 

Stages and Predicates

Stage 1: source

TMApexOneEvent

Stage 2: where

| where EventMessage has "Behavior Monitoring"

Stage 3: extend

| extend DeviceCustomNumber3 = coalesce(column_ifexists("FieldDeviceCustomNumber3", long(null)),DeviceCustomNumber3)

Stage 4: where

| where Event_Type == 2048 or DeviceCustomNumber3 == 403 or DeviceCustomNumber3 == 601

Stage 5: extend

| extend IPCustomEntity = SrcIpAddr, AccountCustomEntity = DstUserName

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
DeviceCustomNumber3eq
  • 403 transforms: cased
  • 601 transforms: cased
EventMessagematch
  • Behavior Monitoring transforms: term
Event_Typeeq
  • 2048 transforms: cased

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

FieldSource
DeviceCustomNumber3extend
AccountCustomEntityextend
IPCustomEntityextend