Cloudflare - Multiple user agents for single source

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Id	fc50076a-0275-43d5-b9dd-38346c061f67
Rulename	Cloudflare - Multiple user agents for single source
Description	Detects requests with different user agents from one source in short timeframe.
Severity	Medium
Tactics	InitialAccess
Techniques	T1190 T1133
Required data connectors	CloudflareDataConnector
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/Cloudflare/Analytic Rules/CloudflareMultipleUAs.yaml
Version	1.0.1
Arm template	fc50076a-0275-43d5-b9dd-38346c061f67.json

KQL

let threshold = 10;
Cloudflare
| where isnotempty(HttpUserAgentOriginal)
| summarize d_ua = dcount(HttpUserAgentOriginal) by SrcIpAddr, bin(TimeGenerated, 3m)
| where d_ua > threshold

YAML

relevantTechniques:
- T1190
- T1133
entityMappings:
- entityType: IP
  fieldMappings:
  - columnName: SrcIpAddr
    identifier: Address
version: 1.0.1
id: fc50076a-0275-43d5-b9dd-38346c061f67
severity: Medium
kind: Scheduled
queryFrequency: 1h
description: |
    'Detects requests with different user agents from one source in short timeframe.'
requiredDataConnectors:
- connectorId: CloudflareDataConnector
  dataTypes:
  - Cloudflare
triggerOperator: gt
name: Cloudflare - Multiple user agents for single source
tactics:
- InitialAccess
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cloudflare/Analytic Rules/CloudflareMultipleUAs.yaml
triggerThreshold: 0
queryPeriod: 1h
query: |
  let threshold = 10;
  Cloudflare
  | where isnotempty(HttpUserAgentOriginal)
  | summarize d_ua = dcount(HttpUserAgentOriginal) by SrcIpAddr, bin(TimeGenerated, 3m)
  | where d_ua > threshold  
status: Available

ARM