Security Event log cleared

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Id	80da0a8f-cfe1-4cd0-a895-8bc1771a720e
Rulename	Security Event log cleared
Description	Checks for event id 1102 which indicates the security event log was cleared. It uses Event Source Name “Microsoft-Windows-Eventlog” to avoid generating false positives from other sources, like AD FS servers for instance.
Severity	Medium
Tactics	DefenseEvasion
Techniques	T1070
Required data connectors	SecurityEvents WindowsForwardedEvents WindowsSecurityEvents
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/Endpoint Threat Protection Essentials/Analytic Rules/SecurityEventLogCleared.yaml
Version	1.1.5
Arm template	80da0a8f-cfe1-4cd0-a895-8bc1771a720e.json

KQL

(union isfuzzy=true
(
SecurityEvent
| where EventID == 1102 and EventSourceName =~ "Microsoft-Windows-Eventlog"
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity
),
(
WindowsEvent
| where EventID == 1102 and Provider =~ "Microsoft-Windows-Eventlog"
| extend Account =  strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
| extend Activity= "1102 - The audit log was cleared."
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity
)
)
| extend Name=tostring(split(Account, "@")[0]), UPNSuffix=tostring(split(Account, "@")[1])
| extend HostName = iif(Computer has '.',substring(Computer,0,indexof(Computer,'.')),Computer) , DnsDomain = iif(Computer has '.',substring(Computer,indexof(Computer,'.')+1),'')

YAML

entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
- entityType: Host
  fieldMappings:
  - identifier: FullName
    columnName: Computer
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: DnsDomain
name: Security Event log cleared
tactics:
- DefenseEvasion
severity: Medium
triggerThreshold: 0
relevantTechniques:
- T1070
id: 80da0a8f-cfe1-4cd0-a895-8bc1771a720e
version: 1.1.5
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Endpoint Threat Protection Essentials/Analytic Rules/SecurityEventLogCleared.yaml
queryFrequency: 1d
triggerOperator: gt
query: |
  (union isfuzzy=true
  (
  SecurityEvent
  | where EventID == 1102 and EventSourceName =~ "Microsoft-Windows-Eventlog"
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity
  ),
  (
  WindowsEvent
  | where EventID == 1102 and Provider =~ "Microsoft-Windows-Eventlog"
  | extend Account =  strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
  | extend Activity= "1102 - The audit log was cleared."
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity
  )
  )
  | extend Name=tostring(split(Account, "@")[0]), UPNSuffix=tostring(split(Account, "@")[1])
  | extend HostName = iif(Computer has '.',substring(Computer,0,indexof(Computer,'.')),Computer) , DnsDomain = iif(Computer has '.',substring(Computer,indexof(Computer,'.')+1),'')  
description: |
  'Checks for event id 1102 which indicates the security event log was cleared.
  It uses Event Source Name "Microsoft-Windows-Eventlog" to avoid generating false positives from other sources, like AD FS servers for instance.'  
requiredDataConnectors:
- connectorId: SecurityEvents
  dataTypes:
  - SecurityEvent
- connectorId: WindowsSecurityEvents
  dataTypes:
  - SecurityEvent
- connectorId: WindowsForwardedEvents
  dataTypes:
  - WindowsEvent
status: Available
queryPeriod: 1d
kind: Scheduled

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/80da0a8f-cfe1-4cd0-a895-8bc1771a720e')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/80da0a8f-cfe1-4cd0-a895-8bc1771a720e')]",
      "properties": {
        "alertRuleTemplateName": "80da0a8f-cfe1-4cd0-a895-8bc1771a720e",
        "customDetails": null,
        "description": "'Checks for event id 1102 which indicates the security event log was cleared.\nIt uses Event Source Name \"Microsoft-Windows-Eventlog\" to avoid generating false positives from other sources, like AD FS servers for instance.'\n",
        "displayName": "Security Event log cleared",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Computer",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "DnsDomain",
                "identifier": "DnsDomain"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Endpoint Threat Protection Essentials/Analytic Rules/SecurityEventLogCleared.yaml",
        "query": "(union isfuzzy=true\n(\nSecurityEvent\n| where EventID == 1102 and EventSourceName =~ \"Microsoft-Windows-Eventlog\"\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity\n),\n(\nWindowsEvent\n| where EventID == 1102 and Provider =~ \"Microsoft-Windows-Eventlog\"\n| extend Account =  strcat(tostring(EventData.SubjectDomainName),\"\\\\\", tostring(EventData.SubjectUserName))\n| extend Activity= \"1102 - The audit log was cleared.\"\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), EventCount = count() by Computer, Account, EventID, Activity\n)\n)\n| extend Name=tostring(split(Account, \"@\")[0]), UPNSuffix=tostring(split(Account, \"@\")[1])\n| extend HostName = iif(Computer has '.',substring(Computer,0,indexof(Computer,'.')),Computer) , DnsDomain = iif(Computer has '.',substring(Computer,indexof(Computer,'.')+1),'')\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1070"
        ],
        "templateVersion": "1.1.5",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}