Query: rule covering Detects when an attacker adds a new AMSI provider via the Windows Registry to bypass AMSI (Antimalware Scan Interface) p
Matching passage: Sigma rule: Detects when an attacker adds a new AMSI provider via the Windows Registry to bypass AMSI (Antimalware Scan Interface) p. Logsource: windows / registry_set. Rule: title: Potential Persistence Via New AMSI Providers - Registry id: 33efc23c-6ea2-4503-8cfe-bdf82ce8f705 status: test description: 'Detects when an attacker adds a new AMSI provider via the Windows Registry to bypass AMSI (Antimalware Scan Interface) protections. Attackers may add custom AMSI providers to persist on the system and evade detection by security software that relies on AMSI for scanning scripts and other content. This technique is often used in conjunction with fileless malware and script-based attacks to maintain persistence while avoiding detection. ' references: - https://persistence-info.github.io/Data/amsi.html - https://github.com/gtworek/PSBits/blob/8d767892f3b17eefa4d0668f5d2df78e844f01d8/FakeAMSI/FakeAMSI.c author: Nasreddine Bencherchali (Nextron Systems) date: 2022-07-21 modified: 2025-10-26 tags: - attack.persistence logsource: category: registry_set product: windows detection: selection: TargetObject|contains: - \SOFTWARE\Microsoft\AMSI\Providers\ - \SOFTWARE\WOW6432Node\Microsoft\AMSI\Providers\ filter_optional_avast: Image: - C:\Program Files\Avast Software\Avast\RegSvr.exe - C:\Program Files\Avast Software\Avast\x86\RegSvr.exe TargetObject|contains: \{FB904E4E-D2C7-4C8D-8492-B620BB9896B1} filter_optional_avg: Image: - C:\Program Files\AVG\Antivirus\RegSvr.exe - C:\Program Files\AVG\Antivirus\x86\RegSvr.exe TargetObject|contains: \{FB904E4E-D2C7-4C8D-8492-B620BB9896B1} filter_optional_avira: Image: C:\Program Files\Avira\Endpoint Protection SDK\endpointprotection.exe TargetObject|contains: \{00000001-3DCC-4B48-A82E-E2071FE58E05} condition: selection and not 1 of filter_optional_* falsepositives: - Legitimate security products adding their own AMSI providers. Filter these according to your environment. level: medium regression_tests_path: regression_data/rules/windows/registry/registry_set/registry_set_persistence_amsi_providers/info.yml
Near-miss passage: Sigma rule: Detects potential abuse of Active Directory Replication Service (ADRS) from a non machine account to request credentials. Logsource: windows / security. Rule: title: Active Directory Replication from Non Machine Account - DcSync Indicator id: 17d619c1-e020-4347-957e-1d1207455c93 related: - id: 611eab06-a145-4dfa-a295-3ccc5c20f59a type: similar status: test description: Detects potential abuse of Active Directory Replication Service (ADRS) from a non machine account to request credentials. references: - https://threathunterplaybook.com/hunts/windows/180815-ADObjectAccessReplication/notebook.html - https://threathunterplaybook.com/library/windows/active_directory_replication.html - https://threathunterplaybook.com/hunts/windows/190101-ADModDirectoryReplication/notebook.html author: Roberto Rodriguez @Cyb3rWard0g date: 2019-07-26 modified: 2026-07-30 tags: - attack.credential-access - attack.t1003.006 logsource: product: windows service: security definition: 'Requirements: A SACL must be configured on the domain NC root object (e.g. DC=domain,DC=com) to generate Event 4662. Add via ADSI Edit: navigate to the domain NC root → Properties → Security → Advanced → Auditing → add an ACE for Everyone, Type: Success, Applies to: This object only, rights: DS-Replication-Get-Changes and DS-Replication-Get-Changes-All. The OS audit subcategory must also be enabled: auditpol /set /subcategory:"Directory Service Access" /success:enable ' detection: selection: EventID: 4662 Properties|contains: - 1131f6ad-9c07-11d1-f79f-00c04fc2dcd2 - 1131f6aa-9c07-11d1-f79f-00c04fc2dcd2 - 9923a32a-3607-11d2-b9be-0000f87a36b2 - 89e95b76-444d-4c62-991a-0facbeda640c filter_main_machine_accounts: SubjectUserName|endswith: $ filter_optional_subject_domain: SubjectDomainName: Window Manager filter_optional_subject_usersid: SubjectUserName|startswith: - NT AUT - MSOL_ condition: selection and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - Unknown level: medium