Exchange AuditLog Disabled | Microsoft Sentinel Analytic Rules

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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%20365/Analytic%20Rules/exchange_auditlogdisabled.yaml
Version	2.0.6
Arm template	194dd92e-d6e7-4249-85a5-273350a7f5ce.json

KQL

OfficeActivity
| where OfficeWorkload =~ "Exchange" 
| 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 AccountName = iff(UserId contains '@', tostring(split(UserId, '@')[0]), UserId)
| extend AccountUPNSuffix = iff(UserId contains '@', tostring(split(UserId, '@')[1]), '')
| extend AccountName = iff(UserId contains '\\', tostring(split(UserId, '\\')[1]), AccountName)
| extend AccountNTDomain = iff(UserId contains '\\', tostring(split(UserId, '\\')[0]), '')

YAML

queryFrequency: 1d
entityMappings:
- fieldMappings:
  - columnName: UserId
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: AccountNTDomain
    identifier: Name
  entityType: Account
- fieldMappings:
  - columnName: ClientIP
    identifier: Address
  entityType: IP
triggerThreshold: 0
triggerOperator: gt
severity: Medium
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20365/Analytic%20Rules/exchange_auditlogdisabled.yaml
query: |
  OfficeActivity
  | where OfficeWorkload =~ "Exchange" 
  | 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 AccountName = iff(UserId contains '@', tostring(split(UserId, '@')[0]), UserId)
  | extend AccountUPNSuffix = iff(UserId contains '@', tostring(split(UserId, '@')[1]), '')
  | extend AccountName = iff(UserId contains '\\', tostring(split(UserId, '\\')[1]), AccountName)
  | extend AccountNTDomain = iff(UserId contains '\\', tostring(split(UserId, '\\')[0]), '')
tactics:
- DefenseEvasion
queryPeriod: 1d
relevantTechniques:
- T1562
requiredDataConnectors:
- connectorId: Office365
  dataTypes:
  - OfficeActivity (Exchange)
id: 194dd92e-d6e7-4249-85a5-273350a7f5ce
kind: Scheduled
version: 2.0.6
description: |
  'Identifies when the exchange audit logging has been disabled which may be an adversary attempt to evade detection or avoid other defenses.'
status: Available
name: Exchange AuditLog Disabled

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/194dd92e-d6e7-4249-85a5-273350a7f5ce')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/194dd92e-d6e7-4249-85a5-273350a7f5ce')]",
      "properties": {
        "alertRuleTemplateName": "194dd92e-d6e7-4249-85a5-273350a7f5ce",
        "customDetails": null,
        "description": "'Identifies when the exchange audit logging has been disabled which may be an adversary attempt to evade detection or avoid other defenses.'\n",
        "displayName": "Exchange AuditLog Disabled",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserId",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountNTDomain",
                "identifier": "Name"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "ClientIP",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20365/Analytic%20Rules/exchange_auditlogdisabled.yaml",
        "query": "OfficeActivity\n| where OfficeWorkload =~ \"Exchange\" \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 AccountName = iff(UserId contains '@', tostring(split(UserId, '@')[0]), UserId)\n| extend AccountUPNSuffix = iff(UserId contains '@', tostring(split(UserId, '@')[1]), '')\n| extend AccountName = iff(UserId contains '\\\\', tostring(split(UserId, '\\\\')[1]), AccountName)\n| extend AccountNTDomain = iff(UserId contains '\\\\', tostring(split(UserId, '\\\\')[0]), '')\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1562"
        ],
        "templateVersion": "2.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}