Detection rules › Kusto

Claroty - Critical baseline deviation

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

Detects Claroty events where EventOriginalType or EventType indicates a Baseline Deviation and EventSeverity is 5, which represents a critical deviation from baseline that may indicate disruptive or unauthorized activity.

MITRE ATT&CK coverage

Rule body kusto

id: 9a8b4321-e2be-449b-8227-a78227441b2a
name: Claroty - Critical baseline deviation
description: Detects Claroty events where EventOriginalType or EventType indicates a Baseline Deviation and EventSeverity
  is 5, which represents a critical deviation from baseline that may indicate disruptive or unauthorized activity.
severity: High
status: Available
requiredDataConnectors:
- connectorId: CefAma
  dataTypes:
  - CommonSecurityLog
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
- Impact
relevantTechniques:
- T1529
- T1565.001
query: |-
  ClarotyEvent
  | where EventOriginalType has 'Baseline Deviation' or EventType has 'Baseline Deviation'
  | where EventSeverity == '5'
  | project TimeGenerated, DstIpAddr
  | extend IPCustomEntity = DstIpAddr
entityMappings:
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
alertDetailsOverride:
  alertDisplayNameFormat: Claroty critical baseline deviation on {{IPCustomEntity}}
  alertDescriptionFormat: Claroty reported a critical baseline deviation for {{IPCustomEntity}}.
version: 1.0.4
kind: Scheduled

Stages and Predicates

Stage 1: source

ClarotyEvent

Stage 2: where

| where EventOriginalType has 'Baseline Deviation' or EventType has 'Baseline Deviation'

Stage 3: where

| where EventSeverity == '5'

Stage 4: project

| project TimeGenerated, DstIpAddr

Stage 5: extend

| extend IPCustomEntity = DstIpAddr

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
EventOriginalTypematch
  • Baseline Deviation transforms: term
EventSeverityeq
  • 5 transforms: cased
EventTypematch
  • Baseline Deviation transforms: term

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
DstIpAddrproject
TimeGeneratedproject
IPCustomEntityextend