Non Domain Controller Active Directory Replication

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Id	b9d2eebc-5dcb-4888-8165-900db44443ab
Rulename	Non Domain Controller Active Directory Replication
Description	This query detects potential attempts by non-computer accounts (non domain controllers) to retrieve/synchronize an active directory object leveraging directory replication services (DRS). A Domain Controller (computer account) would usually be performing these actions in a domain environment. Another detection rule can be created to cover domain controllers accounts doing at rare times. A domain user with privileged permissions to use directory replication services is rare.
Severity	High
Tactics	CredentialAccess
Techniques	T1003
Required data connectors	SecurityEvents WindowsSecurityEvents
Kind	Scheduled
Query frequency	1d
Query period	7d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/NonDCActiveDirectoryReplication.yaml
Version	1.0.4
Arm template	b9d2eebc-5dcb-4888-8165-900db44443ab.json

KQL

// Enter a reference list of hostnames for your DC servers
//let DCServersList = dynamic (["DC01.simulandlabs.com","DC02.simulandlabs.com"]);
SecurityEvent
//| where Computer in (DCServersList)
| where EventID == 4662 and ObjectServer == 'DS'
| where AccountType != 'Machine'
| where Properties has '1131f6aa-9c07-11d1-f79f-00c04fc2dcd2' //DS-Replication-Get-Changes
    or Properties has '1131f6ad-9c07-11d1-f79f-00c04fc2dcd2' //DS-Replication-Get-Changes-All
    or Properties has '89e95b76-444d-4c62-991a-0facbeda640c' //DS-Replication-Get-Changes-In-Filtered-Set
| project TimeGenerated, Account, Activity, Properties, SubjectLogonId, Computer
| join kind=leftouter
(
    SecurityEvent
    //| where Computer in (DCServersList)
    | where EventID == 4624 and LogonType == 3
    | where AccountType != 'Machine'
    | project TargetLogonId, IpAddress
)
on $left.SubjectLogonId == $right.TargetLogonId
| project-reorder TimeGenerated, Computer, Account, IpAddress
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend AccountName = tostring(split(Account, "\\")[0]), AccountNTDomain = tostring(split(Account, "\\")[1])

YAML

description: |
  'This query detects potential attempts by non-computer accounts (non domain controllers) to retrieve/synchronize an active directory object leveraging directory replication services (DRS).
  A Domain Controller (computer account) would usually be performing these actions in a domain environment. Another detection rule can be created to cover domain controllers accounts doing at rare times.
  A domain user with privileged permissions to use directory replication services is rare.'  
kind: Scheduled
tactics:
- CredentialAccess
requiredDataConnectors:
- connectorId: SecurityEvents
  dataTypes:
  - SecurityEvent
- connectorId: WindowsSecurityEvents
  dataTypes:
  - SecurityEvent
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/NonDCActiveDirectoryReplication.yaml
severity: High
name: Non Domain Controller Active Directory Replication
triggerThreshold: 0
queryPeriod: 7d
query: |
  // Enter a reference list of hostnames for your DC servers
  //let DCServersList = dynamic (["DC01.simulandlabs.com","DC02.simulandlabs.com"]);
  SecurityEvent
  //| where Computer in (DCServersList)
  | where EventID == 4662 and ObjectServer == 'DS'
  | where AccountType != 'Machine'
  | where Properties has '1131f6aa-9c07-11d1-f79f-00c04fc2dcd2' //DS-Replication-Get-Changes
      or Properties has '1131f6ad-9c07-11d1-f79f-00c04fc2dcd2' //DS-Replication-Get-Changes-All
      or Properties has '89e95b76-444d-4c62-991a-0facbeda640c' //DS-Replication-Get-Changes-In-Filtered-Set
  | project TimeGenerated, Account, Activity, Properties, SubjectLogonId, Computer
  | join kind=leftouter
  (
      SecurityEvent
      //| where Computer in (DCServersList)
      | where EventID == 4624 and LogonType == 3
      | where AccountType != 'Machine'
      | project TargetLogonId, IpAddress
  )
  on $left.SubjectLogonId == $right.TargetLogonId
  | project-reorder TimeGenerated, Computer, Account, IpAddress
  | extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
  | extend AccountName = tostring(split(Account, "\\")[0]), AccountNTDomain = tostring(split(Account, "\\")[1])  
relevantTechniques:
- T1003
id: b9d2eebc-5dcb-4888-8165-900db44443ab
queryFrequency: 1d
status: Available
triggerOperator: gt
version: 1.0.4
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: Account
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountNTDomain
    identifier: NTDomain
- entityType: Host
  fieldMappings:
  - columnName: Computer
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: NTDomain
- entityType: IP
  fieldMappings:
  - columnName: IpAddress
    identifier: Address

ARM