Google DNS - Multiple errors to same domain

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Id	da04a5d6-e2be-4cba-8cdb-a3f2efa87e9e
Rulename	Google DNS - Multiple errors to same domain
Description	Detects multiple errors to same domain.
Severity	Medium
Tactics	CommandAndControl
Techniques	T1095
Required data connectors	GCPDNSDataConnector
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GoogleCloudPlatformDNS/Analytic Rules/GCPDNSMultipleErrorsQuery.yaml
Version	1.0.0
Arm template	da04a5d6-e2be-4cba-8cdb-a3f2efa87e9e.json

KQL

let threshold = 2;
let err = dynamic(['NXDOMAIN', 'SERVFAIL', 'REFUSED']);
GCPCloudDNS
| where EventResultDetails in~ (err)
| summarize ips = makeset(SrcIpAddr) by Query, bin(TimeGenerated, 10m)
| where array_length(ips) >= threshold
| extend DNSCustomEntity = Query, IPCustomEntity = ips

YAML

kind: Scheduled
queryFrequency: 1h
queryPeriod: 1h
version: 1.0.0
tactics:
- CommandAndControl
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GoogleCloudPlatformDNS/Analytic Rules/GCPDNSMultipleErrorsQuery.yaml
triggerThreshold: 0
description: |
    'Detects multiple errors to same domain.'
severity: Medium
relevantTechniques:
- T1095
id: da04a5d6-e2be-4cba-8cdb-a3f2efa87e9e
name: Google DNS - Multiple errors to same domain
requiredDataConnectors:
- dataTypes:
  - GCPCloudDNS
  connectorId: GCPDNSDataConnector
query: |
  let threshold = 2;
  let err = dynamic(['NXDOMAIN', 'SERVFAIL', 'REFUSED']);
  GCPCloudDNS
  | where EventResultDetails in~ (err)
  | summarize ips = makeset(SrcIpAddr) by Query, bin(TimeGenerated, 10m)
  | where array_length(ips) >= threshold
  | extend DNSCustomEntity = Query, IPCustomEntity = ips  
entityMappings:
- fieldMappings:
  - identifier: DomainName
    columnName: DNSCustomEntity
  entityType: DNS
- fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
  entityType: IP
triggerOperator: gt

ARM