Windows AD Suspicious Attribute Modification

name: Windows AD Suspicious Attribute Modification
id: 5682052e-ce55-4f9f-8d28-59191420b7e0
version: 10
creation_date: '2024-07-01'
modification_date: '2026-05-13'
author: Dean Luxton
status: production
type: TTP
description: 'This detection monitors changes to the following Active Directory attributes: "msDS-AllowedToDelegateTo", "msDS-AllowedToActOnBehalfOfOtherIdentity", "msDS-KeyCredentialLink", "scriptPath", and "msTSInitialProgram".  Modifications to these attributes can indicate potential malicious activity or privilege escalation attempts. Immediate investigation is recommended upon alert.'
data_source:
    - Windows Event Log Security 5136
search: |-
    `wineventlog_security` EventCode=5136 AttributeLDAPDisplayName IN ("msDS-AllowedToDelegateTo","msDS-AllowedToActOnBehalfOfOtherIdentity","scriptPath","msTSInitialProgram") OperationType=%%14674  ```Changes to the attribute "msDS-KeyCredentialLink" are also worth moniroting, however tuning will need to be applied```
      | table _time ObjectClass ObjectDN OpCorrelationID src_user SubjectLogonId DSName AttributeValue AttributeLDAPDisplayName
      | rename SubjectLogonId as TargetLogonId, src_user as initiator, _time as eventTime
      | appendpipe [
      | map search="search `wineventlog_security` EventCode=4624 TargetLogonId=$TargetLogonId$"]
      | stats min(eventTime) as _time values(initiator) as src_user, values(DSName) as targetDomain, values(ObjectDN) as ObjectDN, values(ObjectClass) as ObjectClass, values(src_category) as src_category, values(src_ip) as src_ip values(LogonType) as LogonType values(AttributeValue) as AttributeValue values(AttributeLDAPDisplayName) as AttributeLDAPDisplayName
        BY TargetLogonId
      | rex field=ObjectDN "^CN=(?P<cn>.*?),[A-Z]{2}\="
      | eval dest=if(ObjectClass="computer",cn,null), user=if(ObjectClass="user",cn,null)
      | fields - cn
      | `windows_ad_suspicious_attribute_modification_filter`
how_to_implement: Ensure you are ingesting Active Directory audit logs - specifically event 5136. See lantern article in references for further on how to onboard AD audit data. Ensure the wineventlog_security macro is configured with the correct indexes.
known_false_positives: If key credentials are regularly assigned to users, these events will need to be tuned out.
references:
    - https://trustedsec.com/blog/a-hitchhackers-guide-to-dacl-based-detections-part-1-a
    - https://lantern.splunk.com/Security/Product_Tips/Enterprise_Security/Enabling_an_audit_trail_from_Active_Directory
finding:
    title: $src_user$ has added $AttributeLDAPDisplayName$ ACL rights to $ObjectClass$ $ObjectDN$
    entity:
        field: src_user
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 50
          message: $src_user$ has added $AttributeLDAPDisplayName$ ACL rights to $ObjectClass$ $ObjectDN$
analytic_story:
    - Sneaky Active Directory Persistence Tricks
asset_type: Endpoint
mitre_attack_id:
    - T1222.001
    - T1550
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint