Zscaler - Unexpected update operation

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Id	672e2846-4226-11ec-81d3-0242ac130003
Rulename	Zscaler - Unexpected update operation
Description	Detects unexpected version of update operation.
Severity	Medium
Tactics	InitialAccess
Techniques	T1190 T1133
Required data connectors	ZscalerPrivateAccess
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/ZscalerUnexpectedUpdateOperation.yaml
Version	1.0.0
Arm template	672e2846-4226-11ec-81d3-0242ac130003.json

KQL

ZPAEvent
| where isnotempty(AuditOperationType)
| extend ExpectedVersion1 = extract(@'(expectedVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 2, AuditOldValue)
| extend ExpectedVersion2 = extract(@'(expectedVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 3, AuditOldValue)
| extend NewVersion1 = extract(@'("currentVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 2, AuditNewValue)
| extend NewVersion2 = extract(@'("currentVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 3, AuditNewValue)
| extend Comparision1 = iff(tolong(ExpectedVersion2) > tolong(NewVersion2), 'Unexpected version', 'Expected version')
| extend VersionCheck = iff(tolong(ExpectedVersion1) > tolong(NewVersion1), 'Unexpected version', Comparision1)
| project-away ExpectedVersion1, ExpectedVersion2, NewVersion1, NewVersion2, Comparision1
| extend ProcessCustomEntity = AuditOperationType

YAML

description: |
    'Detects unexpected version of update operation.'
status: Available
queryPeriod: 1h
severity: Medium
triggerOperator: gt
kind: Scheduled
triggerThreshold: 0
relevantTechniques:
- T1190
- T1133
version: 1.0.0
name: Zscaler - Unexpected update operation
queryFrequency: 1h
id: 672e2846-4226-11ec-81d3-0242ac130003
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Zscaler Private Access (ZPA)/Analytic Rules/ZscalerUnexpectedUpdateOperation.yaml
entityMappings:
- fieldMappings:
  - columnName: ProcessCustomEntity
    identifier: ProcessId
  entityType: Process
tactics:
- InitialAccess
requiredDataConnectors:
- dataTypes:
  - ZPAEvent
  connectorId: ZscalerPrivateAccess
query: |
  ZPAEvent
  | where isnotempty(AuditOperationType)
  | extend ExpectedVersion1 = extract(@'(expectedVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 2, AuditOldValue)
  | extend ExpectedVersion2 = extract(@'(expectedVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 3, AuditOldValue)
  | extend NewVersion1 = extract(@'("currentVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 2, AuditNewValue)
  | extend NewVersion2 = extract(@'("currentVersion":")([0-9]+)\.([0-9]+\.[0-9]+)', 3, AuditNewValue)
  | extend Comparision1 = iff(tolong(ExpectedVersion2) > tolong(NewVersion2), 'Unexpected version', 'Expected version')
  | extend VersionCheck = iff(tolong(ExpectedVersion1) > tolong(NewVersion1), 'Unexpected version', Comparision1)
  | project-away ExpectedVersion1, ExpectedVersion2, NewVersion1, NewVersion2, Comparision1
  | extend ProcessCustomEntity = AuditOperationType

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/672e2846-4226-11ec-81d3-0242ac130003')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/672e2846-4226-11ec-81d3-0242ac130003')]",
      "properties": {
        "alertRuleTemplateName": "672e2846-4226-11ec-81d3-0242ac130003",
        "customDetails": null,
        "description": "'Detects unexpected version of update operation.'\n",
        "displayName": "Zscaler - Unexpected update operation",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "ProcessCustomEntity",
                "identifier": "ProcessId"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Zscaler Private Access (ZPA)/Analytic Rules/ZscalerUnexpectedUpdateOperation.yaml",
        "query": "ZPAEvent\n| where isnotempty(AuditOperationType)\n| extend ExpectedVersion1 = extract(@'(expectedVersion\":\")([0-9]+)\\.([0-9]+\\.[0-9]+)', 2, AuditOldValue)\n| extend ExpectedVersion2 = extract(@'(expectedVersion\":\")([0-9]+)\\.([0-9]+\\.[0-9]+)', 3, AuditOldValue)\n| extend NewVersion1 = extract(@'(\"currentVersion\":\")([0-9]+)\\.([0-9]+\\.[0-9]+)', 2, AuditNewValue)\n| extend NewVersion2 = extract(@'(\"currentVersion\":\")([0-9]+)\\.([0-9]+\\.[0-9]+)', 3, AuditNewValue)\n| extend Comparision1 = iff(tolong(ExpectedVersion2) > tolong(NewVersion2), 'Unexpected version', 'Expected version')\n| extend VersionCheck = iff(tolong(ExpectedVersion1) > tolong(NewVersion1), 'Unexpected version', Comparision1)\n| project-away ExpectedVersion1, ExpectedVersion2, NewVersion1, NewVersion2, Comparision1\n| extend ProcessCustomEntity = AuditOperationType\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "techniques": [
          "T1133",
          "T1190"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}