Detect Print Processors Registry Driver Key CreationModification

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Id	7edde3d4-9859-4a00-b93c-b19ddda55320
Rulename	Detect Print Processors Registry Driver Key Creation/Modification
Description	This analytic rule detects any registry value creation or modification of print processor registry Driver key. This will load the executable at startup with print spooler service. This could be an indication of a persistence attempt by an adversary.
Severity	Medium
Tactics	Persistence PrivilegeEscalation
Techniques	T1547
Required data connectors	CiscoSecureEndpoint CrowdStrikeFalconEndpointProtection MicrosoftThreatProtection SentinelOne TrendMicroApexOne TrendMicroApexOneAma VMwareCarbonBlack
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/Malware Protection Essentials/Analytic Rules/PrintProcessersModified.yaml
Version	1.0.0
Arm template	7edde3d4-9859-4a00-b93c-b19ddda55320.json

KQL

// Print Processor Registry Key RegEx
let printProcessorRegistryRegEx = @'HKEY_LOCAL_MACHINE\\SYSTEM\\[A-Za-z0-9]*ControlSet[A-Za-z0-9]*\\Control\\Print\\Environments\\Windows\s[A-Za-z0-9]+\\Print Processors\\[A-Za-z0-9]+\\Driver';
_ASim_RegistryEvent
| where EventType in ('RegistryValueSet', 'RegistryKeyCreated')
| where RegistryKey matches regex printProcessorRegistryRegEx
| project
    TimeGenerated,
    DvcHostname,
    ActorUsername,
    ActorUsernameType,
    ActingProcessId,
    ActingProcessName,
    ActingProcessCommandLine,
    RegistryKey,
    RegistryValue,
    RegistryValueType,
    RegistryValueData
| extend HostName = tostring(split(DvcHostname, '.')[0])
| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
| extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\'))

YAML

name: Detect Print Processors Registry Driver Key Creation/Modification
relevantTechniques:
- T1547
eventGroupingSettings:
  aggregationKind: SingleAlert
requiredDataConnectors:
- dataTypes:
  - CommonSecurityLog
  connectorId: CrowdStrikeFalconEndpointProtection
- dataTypes:
  - SecurityAlert
  connectorId: MicrosoftThreatProtection
- dataTypes:
  - SentinelOne_CL
  connectorId: SentinelOne
- dataTypes:
  - CarbonBlackEvents_CL
  connectorId: VMwareCarbonBlack
- dataTypes:
  - CiscoSecureEndpoint_CL
  connectorId: CiscoSecureEndpoint
- dataTypes:
  - TMApexOneEvent
  connectorId: TrendMicroApexOne
- dataTypes:
  - TMApexOneEvent
  connectorId: TrendMicroApexOneAma
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/PrintProcessersModified.yaml
query: |
  // Print Processor Registry Key RegEx
  let printProcessorRegistryRegEx = @'HKEY_LOCAL_MACHINE\\SYSTEM\\[A-Za-z0-9]*ControlSet[A-Za-z0-9]*\\Control\\Print\\Environments\\Windows\s[A-Za-z0-9]+\\Print Processors\\[A-Za-z0-9]+\\Driver';
  _ASim_RegistryEvent
  | where EventType in ('RegistryValueSet', 'RegistryKeyCreated')
  | where RegistryKey matches regex printProcessorRegistryRegEx
  | project
      TimeGenerated,
      DvcHostname,
      ActorUsername,
      ActorUsernameType,
      ActingProcessId,
      ActingProcessName,
      ActingProcessCommandLine,
      RegistryKey,
      RegistryValue,
      RegistryValueType,
      RegistryValueData
  | extend HostName = tostring(split(DvcHostname, '.')[0])
  | extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
  | extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
  | extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
  | extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
  | extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
  | extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\'))   
tactics:
- Persistence
- PrivilegeEscalation
description: |
    This analytic rule detects any registry value creation or modification of print processor registry Driver key. This will load the executable at startup with print spooler service. This could be an indication of a persistence attempt by an adversary.
entityMappings:
- fieldMappings:
  - columnName: HostName
    identifier: HostName
  - columnName: DnsDomain
    identifier: DnsDomain
  - columnName: NTDomain
    identifier: NTDomain
  entityType: Host
- fieldMappings:
  - columnName: Username
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  - columnName: NTDomain
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: ActingProcessId
    identifier: ProcessId
  - columnName: ActingProcessCommandLine
    identifier: CommandLine
  entityType: Process
- fieldMappings:
  - columnName: RegHive
    identifier: Hive
  - columnName: RegKey
    identifier: Key
  entityType: RegistryKey
- fieldMappings:
  - columnName: RegistryValue
    identifier: Name
  - columnName: RegistryValueData
    identifier: Value
  - columnName: RegistryValueType
    identifier: ValueType
  entityType: RegistryValue
queryFrequency: 1h
alertDetailsOverride:
  alertDescriptionFormat: 'Process {{ActingProcessName}} ProcessId: ({{ActingProcessId}}) modified registry driver key {{RegistryKey}}.'
  alertDisplayNameFormat: Print Processor Registry Driver Keys Modified on {{DvcHostname}} ({{DvcIpAddr}}) by ({{ActorUsername}})
triggerOperator: gt
version: 1.0.0
queryPeriod: 1h
status: Available
kind: Scheduled
severity: Medium
triggerThreshold: 0
id: 7edde3d4-9859-4a00-b93c-b19ddda55320
tags:
- Schema: _ASim_RegistryEvent
  SchemaVersion: 0.1.2

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/7edde3d4-9859-4a00-b93c-b19ddda55320')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/7edde3d4-9859-4a00-b93c-b19ddda55320')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Process {{ActingProcessName}} ProcessId: ({{ActingProcessId}}) modified registry driver key {{RegistryKey}}.",
          "alertDisplayNameFormat": "Print Processor Registry Driver Keys Modified on {{DvcHostname}} ({{DvcIpAddr}}) by ({{ActorUsername}})"
        },
        "alertRuleTemplateName": "7edde3d4-9859-4a00-b93c-b19ddda55320",
        "customDetails": null,
        "description": "This analytic rule detects any registry value creation or modification of print processor registry Driver key. This will load the executable at startup with print spooler service. This could be an indication of a persistence attempt by an adversary.\n",
        "displayName": "Detect Print Processors Registry Driver Key Creation/Modification",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "DnsDomain",
                "identifier": "DnsDomain"
              },
              {
                "columnName": "NTDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Username",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              },
              {
                "columnName": "NTDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "ActingProcessId",
                "identifier": "ProcessId"
              },
              {
                "columnName": "ActingProcessCommandLine",
                "identifier": "CommandLine"
              }
            ]
          },
          {
            "entityType": "RegistryKey",
            "fieldMappings": [
              {
                "columnName": "RegHive",
                "identifier": "Hive"
              },
              {
                "columnName": "RegKey",
                "identifier": "Key"
              }
            ]
          },
          {
            "entityType": "RegistryValue",
            "fieldMappings": [
              {
                "columnName": "RegistryValue",
                "identifier": "Name"
              },
              {
                "columnName": "RegistryValueData",
                "identifier": "Value"
              },
              {
                "columnName": "RegistryValueType",
                "identifier": "ValueType"
              }
            ]
          }
        ],
        "eventGroupingSettings": {
          "aggregationKind": "SingleAlert"
        },
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/PrintProcessersModified.yaml",
        "query": "// Print Processor Registry Key RegEx\nlet printProcessorRegistryRegEx = @'HKEY_LOCAL_MACHINE\\\\SYSTEM\\\\[A-Za-z0-9]*ControlSet[A-Za-z0-9]*\\\\Control\\\\Print\\\\Environments\\\\Windows\\s[A-Za-z0-9]+\\\\Print Processors\\\\[A-Za-z0-9]+\\\\Driver';\n_ASim_RegistryEvent\n| where EventType in ('RegistryValueSet', 'RegistryKeyCreated')\n| where RegistryKey matches regex printProcessorRegistryRegEx\n| project\n    TimeGenerated,\n    DvcHostname,\n    ActorUsername,\n    ActorUsernameType,\n    ActingProcessId,\n    ActingProcessName,\n    ActingProcessCommandLine,\n    RegistryKey,\n    RegistryValue,\n    RegistryValueType,\n    RegistryValueData\n| extend HostName = tostring(split(DvcHostname, '.')[0])\n| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))\n| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\\\')[1]), ActorUsername)\n| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\\\')[0]), ActorUsername)\n| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)\n| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')\n| extend RegHive = tostring(split(RegistryKey, '\\\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\\\'), 1, -1), '\\\\')) \n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence",
          "PrivilegeEscalation"
        ],
        "tags": [
          {
            "Schema": "_ASim_RegistryEvent",
            "SchemaVersion": "0.1.2"
          }
        ],
        "techniques": [
          "T1547"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}