Detection of Specific Hashes in CommonSecurityLog

// Identifies a match in CommonSecurityLog from the Recorded Future Hashes Observed in Underground Virus Testing Sites
let dt_lookBack = 1h;
let ioc_lookBack = 1d;
let fileHashIndicators = ThreatIntelligenceIndicator
| where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()
// Picking up only Recorded Future IOC's that have been observed in undersground testing sites
| where Description == "Recorded Future - HASH - Observed in Underground Virus Testing Sites"
| where Active == true
| where isnotempty(FileHashValue);
// Handle matches against both lower case and uppercase versions of the hash:
(fileHashIndicators | extend  FileHashValue = tolower(FileHashValue)
| union (fileHashIndicators | extend FileHashValue = toupper(FileHashValue)))
| join (
  CommonSecurityLog | where TimeGenerated >= ago(dt_lookBack)
  | where isnotempty(FileHash)
  | extend CommonSecurityLog_TimeGenerated = TimeGenerated
  )
on $left.FileHashValue == $right.FileHash
| where CommonSecurityLog_TimeGenerated >= TimeGenerated and CommonSecurityLog_TimeGenerated < ExpirationDateTime
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
| project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
CommonSecurityLog_TimeGenerated, SourceIP, SourcePort, DestinationIP, DestinationPort, SourceUserID, SourceUserName, DeviceName, DeviceAction, RequestURL, DestinationUserName, DestinationUserID, ApplicationProtocol, Activity, FileHash, AdditionalInformation
| extend AccountName = tostring(split(SourceUserName, "@")[0]), AccountUPNSuffix = tostring(split(SourceUserName, "@")[1])
| extend HostName = tostring(split(DeviceName, ".")[0]), DomainIndex = toint(indexof(DeviceName, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)

relevantTechniques:
- T1587.001
name: Detection of Specific Hashes in CommonSecurityLog
requiredDataConnectors:
- dataTypes:
  - CommonSecurityLog
  connectorId: CEF
- dataTypes:
  - CommonSecurityLog
  connectorId: CefAma
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: SourceUserName
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: FullName
    columnName: DeviceName
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: HostNameDomain
  entityType: Host
- fieldMappings:
  - identifier: Address
    columnName: SourceIP
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: Url
  entityType: URL
triggerThreshold: 0
id: 388e197d-ec9e-46b6-addb-947d74d2a5c4
tactics:
- ResourceDevelopment
version: 1.0.2
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Recorded Future/Analytic Rules/RecordedFutureHashObservedInUndergroundinCommonSecurityLog.yaml
queryPeriod: 1d
kind: Scheduled
queryFrequency: 1h
severity: Medium
status: Available
description: |
    'Identifies a match in CommonSecurityLog from Recorded Future Hash Observed in Underground Virus Testing Sites RiskList.'
query: |
  // Identifies a match in CommonSecurityLog from the Recorded Future Hashes Observed in Underground Virus Testing Sites
  let dt_lookBack = 1h;
  let ioc_lookBack = 1d;
  let fileHashIndicators = ThreatIntelligenceIndicator
  | where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()
  // Picking up only Recorded Future IOC's that have been observed in undersground testing sites
  | where Description == "Recorded Future - HASH - Observed in Underground Virus Testing Sites"
  | where Active == true
  | where isnotempty(FileHashValue);
  // Handle matches against both lower case and uppercase versions of the hash:
  (fileHashIndicators | extend  FileHashValue = tolower(FileHashValue)
  | union (fileHashIndicators | extend FileHashValue = toupper(FileHashValue)))
  | join (
    CommonSecurityLog | where TimeGenerated >= ago(dt_lookBack)
    | where isnotempty(FileHash)
    | extend CommonSecurityLog_TimeGenerated = TimeGenerated
    )
  on $left.FileHashValue == $right.FileHash
  | where CommonSecurityLog_TimeGenerated >= TimeGenerated and CommonSecurityLog_TimeGenerated < ExpirationDateTime
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
  CommonSecurityLog_TimeGenerated, SourceIP, SourcePort, DestinationIP, DestinationPort, SourceUserID, SourceUserName, DeviceName, DeviceAction, RequestURL, DestinationUserName, DestinationUserID, ApplicationProtocol, Activity, FileHash, AdditionalInformation
  | extend AccountName = tostring(split(SourceUserName, "@")[0]), AccountUPNSuffix = tostring(split(SourceUserName, "@")[1])
  | extend HostName = tostring(split(DeviceName, ".")[0]), DomainIndex = toint(indexof(DeviceName, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)  
triggerOperator: gt

{
  "$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/388e197d-ec9e-46b6-addb-947d74d2a5c4')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/388e197d-ec9e-46b6-addb-947d74d2a5c4')]",
      "properties": {
        "alertRuleTemplateName": "388e197d-ec9e-46b6-addb-947d74d2a5c4",
        "customDetails": null,
        "description": "'Identifies a match in CommonSecurityLog from Recorded Future Hash Observed in Underground Virus Testing Sites RiskList.'\n",
        "displayName": "Detection of Specific Hashes in CommonSecurityLog",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "SourceUserName",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SourceIP",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Url",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Recorded Future/Analytic Rules/RecordedFutureHashObservedInUndergroundinCommonSecurityLog.yaml",
        "query": "// Identifies a match in CommonSecurityLog from the Recorded Future Hashes Observed in Underground Virus Testing Sites\nlet dt_lookBack = 1h;\nlet ioc_lookBack = 1d;\nlet fileHashIndicators = ThreatIntelligenceIndicator\n| where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()\n// Picking up only Recorded Future IOC's that have been observed in undersground testing sites\n| where Description == \"Recorded Future - HASH - Observed in Underground Virus Testing Sites\"\n| where Active == true\n| where isnotempty(FileHashValue);\n// Handle matches against both lower case and uppercase versions of the hash:\n(fileHashIndicators | extend  FileHashValue = tolower(FileHashValue)\n| union (fileHashIndicators | extend FileHashValue = toupper(FileHashValue)))\n| join (\n  CommonSecurityLog | where TimeGenerated >= ago(dt_lookBack)\n  | where isnotempty(FileHash)\n  | extend CommonSecurityLog_TimeGenerated = TimeGenerated\n  )\non $left.FileHashValue == $right.FileHash\n| where CommonSecurityLog_TimeGenerated >= TimeGenerated and CommonSecurityLog_TimeGenerated < ExpirationDateTime\n| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId\n| project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,\nCommonSecurityLog_TimeGenerated, SourceIP, SourcePort, DestinationIP, DestinationPort, SourceUserID, SourceUserName, DeviceName, DeviceAction, RequestURL, DestinationUserName, DestinationUserID, ApplicationProtocol, Activity, FileHash, AdditionalInformation\n| extend AccountName = tostring(split(SourceUserName, \"@\")[0]), AccountUPNSuffix = tostring(split(SourceUserName, \"@\")[1])\n| extend HostName = tostring(split(DeviceName, \".\")[0]), DomainIndex = toint(indexof(DeviceName, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1587.001"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "ResourceDevelopment"
        ],
        "techniques": [
          "T1587"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}