Query: write Sigma for Detects changes to "DsrmAdminLogonBehavior" registry value. During a Domain Controller (DC) promotion, administrators cr
Matching passage: Sigma rule: Detects changes to "DsrmAdminLogonBehavior" registry value. During a Domain Controller (DC) promotion, administrators cr. Logsource: windows / registry_set. Rule: title: Directory Service Restore Mode(DSRM) Registry Value Tampering id: b61e87c0-50db-4b2e-8986-6a2be94b33b0 related: - id: 53ad8e36-f573-46bf-97e4-15ba5bf4bb51 type: similar status: test description: 'Detects changes to "DsrmAdminLogonBehavior" registry value. During a Domain Controller (DC) promotion, administrators create a Directory Services Restore Mode (DSRM) local administrator account with a password that rarely changes. The DSRM account is an “Administrator” account that logs in with the DSRM mode when the server is booting up to restore AD backups or recover the server from a failure. Attackers could abuse DSRM account to maintain their persistence and access to the organization''s Active Directory. If the "DsrmAdminLogonBehavior" value is set to "0", the administrator account can only be used if the DC starts in DSRM. If the "DsrmAdminLogonBehavior" value is set to "1", the administrator account can only be used if the local AD DS service is stopped. If the "DsrmAdminLogonBehavior" value is set to "2", the administrator account can always be used. ' references: - https://adsecurity.org/?p=1785 - https://www.sentinelone.com/blog/detecting-dsrm-account-misconfigurations/ - https://book.hacktricks.xyz/windows-hardening/active-directory-methodology/dsrm-credentials author: Nischal Khadgi date: 2024-07-11 tags: - attack.credential-access - attack.persistence - attack.defense-impairment - attack.t1556 logsource: category: registry_set product: windows detection: selection: TargetObject|endswith: \Control\Lsa\DsrmAdminLogonBehavior filter_main_default_value: Details: DWORD (0x00000000) condition: selection and not 1 of filter_main_* falsepositives: - Unknown level: high
Near-miss passage: Sigma rule: Detects the execution of rundll32.exe with the oledb32.dll library to open a UDL file. Threat actors can abuse this tech. Logsource: windows / process_creation. Rule: title: Potentially Suspicious Rundll32.EXE Execution of UDL File id: 0ea52357-cd59-4340-9981-c46c7e900428 status: test description: 'Detects the execution of rundll32.exe with the oledb32.dll library to open a UDL file. Threat actors can abuse this technique as a phishing vector to capture authentication credentials or other sensitive data. ' references: - https://trustedsec.com/blog/oops-i-udld-it-again author: '@kostastsale' date: 2024-08-16 tags: - attack.execution - attack.command-and-control - attack.stealth - attack.t1218.011 - attack.t1071 logsource: category: process_creation product: windows detection: selection_parent: ParentImage|endswith: \explorer.exe selection_img: - Image|endswith: \rundll32.exe - OriginalFileName: RUNDLL32.EXE selection_cli: CommandLine|contains|all: - oledb32.dll - ',OpenDSLFile ' - \\Users\\*\\Downloads\\ CommandLine|endswith: .udl condition: all of selection_* falsepositives: - UDL files serve as a convenient and flexible tool for managing and testing database connections in various development and administrative scenarios. level: medium