Elastic Defend high stable eql
Potential LogonUser API Hooking
Identifies attempts to hook LogonUser API via memory modification. This may indicate an attempt to steal credentials passed for authentication verification via this API.
Detection Logic
api where process.Ext.api.name in ("WriteProcessMemory", "VirtualProtect") and
process.Ext.api.metadata.target_address_name like "advapi32.dll!LogonUser*" and process.executable != null and
not process.thread.Ext.call_stack_final_user_module.name in ("Kernel", "Unknown", "Undetermined") and
not process.thread.Ext.call_stack_final_user_module.path in ("c:\\windows\\syswow64\\werfault.exe", "c:\\windows\\system32\\werfault.exe") and
not _arraysearch(process.thread.Ext.call_stack_final_user_module.code_signature, $entry, $entry.trusted == true or $entry.status like "errorCode_endpoint*") and
process.thread.Ext.call_stack_final_user_module.hash.sha256 != "fdfc853b183d682c912e6487a64dbaea98f8d09207a55d0a512e550c988d6273" and
not _arraysearch(process.thread.Ext.call_stack, $entry, $entry.symbol_info like "c:\\windows\\system32\\ntdll.dll!LdrLoadDll*") and
not process.thread.Ext.call_stack_final_user_module.path :
("?:\\program files\\avg\\antivirus\\aswhook.dll",
"?:\\program files\\avg\\antivirus\\x86\\aswhook.dll",
"?:\\program files\\avast software\\avast\\aswhook.dll",
"?:\\program files\\avast software\\avast\\x86\\aswhook.dll",
"?:\\windows\\assembly\\nativeimages_*\\microsoft.powershell.commands.management.ni.dll") and
not process.executable : ("C:\\Program Files (x86)\\Common Files\\Adobe\\ARM\\1.0\\AdobeARM.exe",
"C:\\Program Files (x86)\\Common Files\\Adobe\\Adobe Desktop Common\\IPCBox\\AdobeIPCBroker.exe",
"C:\\Program Files\\Avast Software\\Browser\\Application\\AvastBrowserProtect.exe") Field Validations
Loading…
Comments (0)
Loading comments...