Exchange AuditLog disabled

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Id	194dd92e-d6e7-4249-85a5-273350a7f5ce
Rulename	Exchange AuditLog disabled
Description	Identifies when the exchange audit logging has been disabled which may be an adversary attempt to evade detection or avoid other defenses.
Severity	Medium
Tactics	DefenseEvasion
Techniques	T1562
Required data connectors	Office365
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/exchange_auditlogdisabled.yaml
Version	2.0.1
Arm template	194dd92e-d6e7-4249-85a5-273350a7f5ce.json

KQL

OfficeActivity
| where UserType in~ ("Admin","DcAdmin")
// Only admin or global-admin can disable audit logging
| where Operation =~ "Set-AdminAuditLogConfig"
| extend AdminAuditLogEnabledValue = tostring(parse_json(tostring(parse_json(tostring(array_slice(parse_json(Parameters),3,3)))[0])).Value)
| where AdminAuditLogEnabledValue =~ "False"
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), OperationCount = count() by Operation, UserType, UserId, ClientIP, ResultStatus, Parameters, AdminAuditLogEnabledValue
| extend timestamp = StartTimeUtc, AccountCustomEntity = UserId, IPCustomEntity = ClientIP

YAML

severity: Medium
queryFrequency: 1d
relevantTechniques:
- T1562
tactics:
- DefenseEvasion
kind: Scheduled
query: |
  OfficeActivity
  | where UserType in~ ("Admin","DcAdmin")
  // Only admin or global-admin can disable audit logging
  | where Operation =~ "Set-AdminAuditLogConfig"
  | extend AdminAuditLogEnabledValue = tostring(parse_json(tostring(parse_json(tostring(array_slice(parse_json(Parameters),3,3)))[0])).Value)
  | where AdminAuditLogEnabledValue =~ "False"
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), OperationCount = count() by Operation, UserType, UserId, ClientIP, ResultStatus, Parameters, AdminAuditLogEnabledValue
  | extend timestamp = StartTimeUtc, AccountCustomEntity = UserId, IPCustomEntity = ClientIP  
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/exchange_auditlogdisabled.yaml
queryPeriod: 1d
status: Available
version: 2.0.1
name: Exchange AuditLog disabled
requiredDataConnectors:
- dataTypes:
  - OfficeActivity
  connectorId: Office365
triggerOperator: gt
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: AccountCustomEntity
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
id: 194dd92e-d6e7-4249-85a5-273350a7f5ce
description: |
  'Identifies when the exchange audit logging has been disabled which may be an adversary attempt
  to evade detection or avoid other defenses.'  
triggerThreshold: 0

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/194dd92e-d6e7-4249-85a5-273350a7f5ce')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/194dd92e-d6e7-4249-85a5-273350a7f5ce')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01-preview",
      "properties": {
        "displayName": "Exchange AuditLog disabled",
        "description": "'Identifies when the exchange audit logging has been disabled which may be an adversary attempt\nto evade detection or avoid other defenses.'\n",
        "severity": "Medium",
        "enabled": true,
        "query": "OfficeActivity\n| where UserType in~ (\"Admin\",\"DcAdmin\")\n// Only admin or global-admin can disable audit logging\n| where Operation =~ \"Set-AdminAuditLogConfig\"\n| extend AdminAuditLogEnabledValue = tostring(parse_json(tostring(parse_json(tostring(array_slice(parse_json(Parameters),3,3)))[0])).Value)\n| where AdminAuditLogEnabledValue =~ \"False\"\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), OperationCount = count() by Operation, UserType, UserId, ClientIP, ResultStatus, Parameters, AdminAuditLogEnabledValue\n| extend timestamp = StartTimeUtc, AccountCustomEntity = UserId, IPCustomEntity = ClientIP\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1562"
        ],
        "alertRuleTemplateName": "194dd92e-d6e7-4249-85a5-273350a7f5ce",
        "customDetails": null,
        "entityMappings": [
          {
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "FullName"
              }
            ],
            "entityType": "Account"
          },
          {
            "fieldMappings": [
              {
                "columnName": "IPCustomEntity",
                "identifier": "Address"
              }
            ],
            "entityType": "IP"
          }
        ],
        "templateVersion": "2.0.1",
        "status": "Available",
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft 365/Analytic Rules/exchange_auditlogdisabled.yaml"
      }
    }
  ]
}