Audit policy manipulation using auditpol utility

id: 66276b14-32c5-4226-88e3-080dacc31ce1
name: Audit policy manipulation using auditpol utility
description: |
   This detects attempts to manipulate audit policies using auditpol command.
   This technique was seen in relation to Solorigate attack but the results can indicate potential malicious activity used in different attacks.
   The process name in each data source is commented out as an adversary could rename it. It is advisable to keep process name commented but if the results show unrelated false positives, users may want to uncomment it.
   Refer to auditpol syntax: https://docs.microsoft.com/windows-server/administration/windows-commands/auditpol  
   Refer to our M365 blog for details on use during the Solorigate attack:
   https://www.microsoft.com/security/blog/2021/01/20/deep-dive-into-the-solorigate-second-stage-activation-from-sunburst-to-teardrop-and-raindrop/
severity: Medium
requiredDataConnectors:
  - connectorId: SecurityEvents
    dataTypes:
      - SecurityEvent
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceProcessEvents
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Execution
relevantTechniques:
  - T1204
tags:
  - Solorigate
  - NOBELIUM
query: |
  let timeframe = 1d;
  let AccountAllowList = dynamic(['SYSTEM']);
  let SubCategoryList = dynamic(["Logoff", "Account Lockout", "User Account Management", "Authorization Policy Change"]); // Add any Category in the list to be allowed or disallowed
  let tokens = dynamic(["clear", "remove", "success:disable","failure:disable"]); 
  (union isfuzzy=true
  (
  SecurityEvent
  | where TimeGenerated >= ago(timeframe)
  //| where Process =~ "auditpol.exe" 
  | where CommandLine has_any (tokens)
  | where AccountType !~ "Machine" and Account !in~ (AccountAllowList)
  | parse CommandLine with * "/subcategory:" subcategorytoken
  | extend SubCategory = tostring(split(subcategorytoken, "\"")[1]) , Toggle =  tostring(split(subcategorytoken, "\"")[2])
  | where SubCategory in~ (SubCategoryList) //use in~ for inclusion or !in~ for exclusion
  | where Toggle !in~ ("/failure:disable", " /success:enable /failure:disable") // use this filter if required to exclude certain toggles
  | project TimeGenerated, Computer, Account, SubjectDomainName, SubjectUserName, Process, ParentProcessName, CommandLine, SubCategory, Toggle
  | extend timestamp = TimeGenerated, AccountName = SubjectUserName, AccountDomain = SubjectDomainName, DeviceName = Computer
  ),
  (
  DeviceProcessEvents
  | where TimeGenerated >= ago(timeframe)
  // | where InitiatingProcessFileName =~ "auditpol.exe" 
  | where InitiatingProcessCommandLine has_any (tokens)
  | where AccountName !in~ (AccountAllowList)
  | parse InitiatingProcessCommandLine with * "/subcategory:" subcategorytoken
  | extend SubCategory = tostring(split(subcategorytoken, "\"")[1]) , Toggle =  tostring(split(subcategorytoken, "\"")[2])
  | where SubCategory in~ (SubCategoryList) //use in~ for inclusion or !in~ for exclusion
  | where Toggle !in~ ("/failure:disable", " /success:enable /failure:disable") // use this filter if required to exclude certain toggles
  | project TimeGenerated, DeviceName, AccountName, InitiatingProcessAccountDomain, InitiatingProcessAccountName, InitiatingProcessFileName, InitiatingProcessParentFileName,  InitiatingProcessCommandLine, SubCategory, Toggle
  | extend timestamp = TimeGenerated, AccountName = InitiatingProcessAccountName, AccountDomain = InitiatingProcessAccountDomain
  ),
  (
  Event
  | where TimeGenerated > ago(timeframe)
  | where Source == "Microsoft-Windows-Sysmon"
  | where EventID == 1
  | extend EventData = parse_xml(EventData).DataItem.EventData.Data
  | mv-expand bagexpansion=array EventData
  | evaluate bag_unpack(EventData)
  | extend Key=tostring(['@Name']), Value=['#text']
  | evaluate pivot(Key, any(Value), TimeGenerated, Source, EventLog, Computer, EventLevel, EventLevelName, EventID, UserName, RenderedDescription, MG, ManagementGroupName, Type, _ResourceId)
  // | where OriginalFileName =~ "auditpol.exe"
  | where CommandLine has_any (tokens)
  | where User !in~ (AccountAllowList)
  | parse CommandLine with * "/subcategory:" subcategorytoken
  | extend SubCategory = tostring(split(subcategorytoken, "\"")[1]) , Toggle =  tostring(split(subcategorytoken, "\"")[2])
  | where SubCategory in~ (SubCategoryList) //use in~ for inclusion or !in~ for exclusion
  | where Toggle !in~ ("/failure:disable", " /success:enable /failure:disable") // use this filter if required to exclude certain toggles
  | project TimeGenerated, Computer, User, Process, ParentImage, CommandLine, SubCategory, Toggle
  | extend timestamp = TimeGenerated, AccountName = tostring(split(User, @'\')[1]), AccountUPNSuffix = tostring(split(User, @'\')[0]), DeviceName = Computer
  )
  )
  | extend Account = strcat(AccountDomain, "\\", AccountName)
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: Account
      - identifier: Name
        columnName: AccountName
      - identifier: NTDomain
        columnName: AccountDomain
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: DeviceName
version: 1.2.3
kind: Scheduled
metadata:
    source:
        kind: Community
    author:
        name: Microsoft Security Research
    support:
        tier: Community
    categories:
        domains: [ "Security - Others" ]