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Cyble Vision Alerts Discovered Subdomain

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
low
Time window
30m
Source
github.com/Azure/Azure-Sentinel

'Triggers when a new subdomain is detected for a monitored keyword/domain.'

MITRE ATT&CK coverage

TacticTechniques
ReconnaissanceT1595 Active Scanning

Rule body kusto

id: 7a0f79cc-8d28-44b5-ac1e-6176565bb7b8
name: Cyble Vision Alerts Discovered Subdomain
description: |
  'Triggers when a new subdomain is detected for a monitored keyword/domain.'
severity: Low
status: Available
requiredDataConnectors:
- connectorId: CybleVisionAlerts
  dataTypes:
  - CybleVisionAlerts_CL
enabled: true
queryfrequency: 30m
queryPeriod: 30m
triggerOperator: GreaterThan
triggerThreshold: 0
eventGroupingSettings:
  aggregationKind: AlertPerResult
tactics:
- Reconnaissance
relevantTechniques:
- T1595
query: |
  Alerts_subdomains  
  | where Service == "subdomains" 
  | extend MappedSeverity = Severity
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: false
    reopenClosedIncident: false
    lookbackDuration: PT5H
    matchingMethod: AllEntities
  alertDetailsOverride:
  alertDisplayNameFormat: New Subdomain Detected {{SD_Subdomain}}
  alertDescriptionFormat: |
    A new subdomain was discovered for monitored domain/keyword. Keyword {{SD_KeywordName}} Bucket {{SD_BucketName}} Severity {{MappedSeverity}} This may represent new attack surface exposure or infrastructure expansion.
customDetails:
  MappedSeverity: Severity
  Status: Status
  AlertID: AlertID
  Service: Service
  SD_Subdomain: SD_Subdomain
  SD_KeywordName: KeywordName
  SD_EntityID: EntityID
  SD_BucketName: BucketName
entityMappings:
- entityType: DNS
  fieldMappings:
  - identifier: DomainName
    columnName: SD_Subdomain
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: source

Alerts_subdomains

Stage 2: where

| where Service == "subdomains"

Stage 3: extend

| extend MappedSeverity = Severity

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
Serviceeq
  • subdomains 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
MappedSeverityextend