Detect Windows Update Disabled from Registry

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Id	f1443a87-78d5-40c3-b051-f468f0f2def0
Rulename	Detect Windows Update Disabled from Registry
Description	This analytic rule detects any registry value creation or modification of Windows Update registry keys to disable Windows Update. This could be an indication of defense evasion by an adversary on a compromised host.
Severity	Medium
Tactics	DefenseEvasion
Techniques	T1562
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/WindowsUpdateDisabled.yaml
Version	1.0.0
Arm template	f1443a87-78d5-40c3-b051-f468f0f2def0.json

KQL

// List of Windows Firewall registry keys to monitor
let windowsUpdateRegistryList = dynamic([
  'HKEY_LOCAL_MACHINE\\Software\\Policies\\Microsoft\\Windows\\WindowsUpdate',
  'HKEY_LOCAL_MACHINE\\Software\\Policies\\Microsoft\\Windows\\WindowsUpdate\\AU'
  ]);
_ASim_RegistryEvent
| where EventType in ('RegistryValueSet', 'RegistryKeyCreated') 
| where RegistryKey has_any (windowsUpdateRegistryList) 
| where RegistryValue has_any ('AUOptions', 'NoAutoUpdate') and RegistryValueData == '1'
| 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

alertDetailsOverride:
  alertDescriptionFormat: Windows Update Disabled from Registry {{RegKey}} on {{HostName}} by {{Username}}
  alertDisplayNameFormat: Windows Update Disabled from Registry on {{HostName}}
description: |
    This analytic rule detects any registry value creation or modification of Windows Update registry keys to disable Windows Update. This could be an indication of defense evasion by an adversary on a compromised host.
kind: Scheduled
tactics:
- DefenseEvasion
requiredDataConnectors:
- connectorId: CrowdStrikeFalconEndpointProtection
  dataTypes:
  - CommonSecurityLog
- connectorId: MicrosoftThreatProtection
  dataTypes:
  - SecurityAlert
- connectorId: SentinelOne
  dataTypes:
  - SentinelOne_CL
- connectorId: VMwareCarbonBlack
  dataTypes:
  - CarbonBlackEvents_CL
- connectorId: CiscoSecureEndpoint
  dataTypes:
  - CiscoSecureEndpoint_CL
- connectorId: TrendMicroApexOne
  dataTypes:
  - TMApexOneEvent
- connectorId: TrendMicroApexOneAma
  dataTypes:
  - TMApexOneEvent
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/WindowsUpdateDisabled.yaml
severity: Medium
name: Detect Windows Update Disabled from Registry
triggerThreshold: 0
queryPeriod: 1h
query: |
  // List of Windows Firewall registry keys to monitor
  let windowsUpdateRegistryList = dynamic([
    'HKEY_LOCAL_MACHINE\\Software\\Policies\\Microsoft\\Windows\\WindowsUpdate',
    'HKEY_LOCAL_MACHINE\\Software\\Policies\\Microsoft\\Windows\\WindowsUpdate\\AU'
    ]);
  _ASim_RegistryEvent
  | where EventType in ('RegistryValueSet', 'RegistryKeyCreated') 
  | where RegistryKey has_any (windowsUpdateRegistryList) 
  | where RegistryValue has_any ('AUOptions', 'NoAutoUpdate') and RegistryValueData == '1'
  | 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), '\\'))   
relevantTechniques:
- T1562
id: f1443a87-78d5-40c3-b051-f468f0f2def0
queryFrequency: 1h
status: Available
version: 1.0.0
triggerOperator: gt
eventGroupingSettings:
  aggregationKind: singleAlert
tags:
- Schema: _ASim_RegistryEvent
  SchemaVersion: 0.1.2
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

ARM