Zscaler - Unexpected event count of rejects by policy

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Id	593e3e2a-43ce-11ec-81d3-0242ac130003
Rulename	Zscaler - Unexpected event count of rejects by policy
Description	Detects unexpected event count of rejects by policy.
Severity	High
Tactics	InitialAccess
Techniques	T1078 T1133
Required data connectors	CustomLogsAma
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/Zscaler Private Access (ZPA)/Analytic Rules/ZscalerUnexpectedCountEventResult.yaml
Version	1.0.2
Arm template	593e3e2a-43ce-11ec-81d3-0242ac130003.json

KQL

let threshold = 1000;
ZPAEvent
| where EventResult has "REJECTED_BY_POLICY"
| summarize rejected = count() by EventResult, DstUserName
| where rejected > threshold
| extend AccountCustomEntity = DstUserName

YAML

name: Zscaler - Unexpected event count of rejects by policy
query: |
  let threshold = 1000;
  ZPAEvent
  | where EventResult has "REJECTED_BY_POLICY"
  | summarize rejected = count() by EventResult, DstUserName
  | where rejected > threshold
  | extend AccountCustomEntity = DstUserName  
queryFrequency: 1h
triggerOperator: gt
requiredDataConnectors:
- datatypes:
  - ZPA_CL
  connectorId: CustomLogsAma
status: Available
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountCustomEntity
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Zscaler Private Access (ZPA)/Analytic Rules/ZscalerUnexpectedCountEventResult.yaml
description: |
    'Detects unexpected event count of rejects by policy.'
version: 1.0.2
id: 593e3e2a-43ce-11ec-81d3-0242ac130003
kind: Scheduled
relevantTechniques:
- T1078
- T1133
severity: High
tactics:
- InitialAccess
queryPeriod: 1h

ARM