Detection rules › Kusto

Process-Level Anomaly

This is a third-party alert feed, not a detection over modeled telemetry. The vendor product raised the finding; this rule forwards it into the SIEM. It is searchable for reference but is excluded from the detection-rule browse and the ATT&CK coverage matrix.

Status
available
Severity
medium
Time window
1d
Group by
application
Source
github.com/Azure/Azure-Sentinel

'Triggers an incident when the same process name appears in 50 or more alerts across multiple devices, suggesting widespread activity.'

MITRE ATT&CK coverage

Rule body kusto

id: 3fa85f64-5717-4562-b3fc-2c963f66afa6
name: Process-Level Anomaly
description: |
  'Triggers an incident when the same process name appears in 50 or more alerts across multiple devices, suggesting widespread activity.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: MorphisecCCF
    dataTypes:
      - Morphisec
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
suppressionDuration: 5h
suppressionEnabled: false
tactics:
  - Execution
  - DefenseEvasion
relevantTechniques:
  - T1059
  - T1204
query: |
  MorphisecAlerts_CL
  | where threatMessageArrivalTime >= ago(24h)
  | summarize 
      AlertCount = dcount(id),
      DeviceCount = dcount(hostname)
      by application
  | where AlertCount >= 50 and DeviceCount > 1
customDetails:
  ProcessName: application
eventGroupingSettings:
  aggregationKind: SingleAlert
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: false
    reopenClosedIncident: false
    lookbackDuration: 5h
    matchingMethod: AllEntities
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: source

MorphisecAlerts_CL

Stage 2: where

| where threatMessageArrivalTime >= ago(24h)

Stage 3: summarize

| summarize 
    AlertCount = dcount(id),
    DeviceCount = dcount(hostname)
    by application
Threshold
ge 50

Stage 4: where

| where AlertCount >= 50 and DeviceCount > 1

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
AlertCountge
  • 50 transforms: cased
DeviceCountgt
  • 1 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
AlertCountsummarize
DeviceCountsummarize
applicationsummarize