Query: rule covering Detects the execution of netsh with "add helper" flag in order to add a custom helper DLL. This technique can be abused
Matching passage: Sigma rule: Detects the execution of netsh with "add helper" flag in order to add a custom helper DLL. This technique can be abused. Logsource: windows / process_creation. Rule: title: Potential Persistence Via Netsh Helper DLL id: 56321594-9087-49d9-bf10-524fe8479452 related: - id: c90362e0-2df3-4e61-94fe-b37615814cb1 type: similar - id: e7b18879-676e-4a0e-ae18-27039185a8e7 type: similar status: test description: 'Detects the execution of netsh with "add helper" flag in order to add a custom helper DLL. This technique can be abused to add a malicious helper DLL that can be used as a persistence proxy that gets called when netsh.exe is executed. ' references: - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1546.007/T1546.007.md - https://github.com/outflanknl/NetshHelperBeacon - https://web.archive.org/web/20160928212230/https://www.adaptforward.com/2016/09/using-netshell-to-execute-evil-dlls-and-persist-on-a-host/ author: Victor Sergeev, oscd.community date: 2019-10-25 modified: 2023-11-28 tags: - attack.privilege-escalation - attack.persistence - attack.t1546.007 - attack.s0108 logsource: category: process_creation product: windows detection: selection_img: - OriginalFileName: netsh.exe - Image|endswith: \netsh.exe selection_cli: CommandLine|contains|all: - add - helper condition: all of selection_* falsepositives: - Unknown level: medium
Near-miss 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