Query: Sigma YAML for windows / process_access
Matching passage: Sigma rule: Detects suspicious process access to LSASS.exe from processes located in uncommon locations with dbgcore.dll or dbghelp.. Logsource: windows / process_access. Rule: title: Suspicious Process Access to LSASS with Dbgcore/Dbghelp DLLs id: 9f5c1d59-33be-4e60-bcab-85d2f566effd related: - id: 416bc4a2-7217-4519-8dc7-c3271817f1d5 type: similar status: experimental description: 'Detects suspicious process access to LSASS.exe from processes located in uncommon locations with dbgcore.dll or dbghelp.dll in the call trace. These DLLs contain functions like MiniDumpWriteDump that can be abused for credential dumping purposes. While modern tools like Mimikatz have moved to using ntdll.dll, dbgcore.dll and dbghelp.dll are still used by basic credential dumping utilities and legacy tools for LSASS memory access and process suspension techniques. ' references: - https://www.splunk.com/en_us/blog/security/you-bet-your-lsass-hunting-lsass-access.html - https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/nf-minidumpwritedump author: Swachchhanda Shrawan Poudel (Nextron Systems) date: 2025-11-27 tags: - attack.credential-access - attack.defense-impairment - attack.t1003.001 - attack.t1685 logsource: category: process_access product: windows detection: selection_lsass_calltrace: TargetImage|endswith: \lsass.exe CallTrace|contains: - dbgcore.dll - dbghelp.dll selection_susp_location: SourceImage|contains: - :\Perflogs\ - :\Temp\ - :\Users\Public\ - \$Recycle.Bin\ - \AppData\Roaming\ - \Contacts\ - \Desktop\ - \Documents\ - \Downloads\ - \Favorites\ - \Favourites\ - \inetpub\wwwroot\ - \Music\ - \Pictures\ - \Start Menu\Programs\Startup\ - \Users\Default\ - \Videos\ - \Windows\Temp\ condition: all of selection_* falsepositives: - Possibly during software installation or update processes level: high regression_tests_path: regression_data/rules/windows/process_access/proc_access_win_susp_dbgcore_dbghelp_load/info.yml
Near-miss passage: Sigma rule: Detects network connections to Visual Studio Code tunnel domains initiated by a process on a system. Attackers can abuse. Logsource: windows / network_connection. Rule: title: Network Connection Initiated To Visual Studio Code Tunnels Domain id: 4b657234-038e-4ad5-997c-4be42340bce4 related: - id: 9501f8e6-8e3d-48fc-a8a6-1089dd5d7ef4 type: similar - id: b3e6418f-7c7a-4fad-993a-93b65027a9f1 type: similar - id: 1cb0c6ce-3d00-44fc-ab9c-6d6d577bf20b type: similar status: test description: 'Detects network connections to Visual Studio Code tunnel domains initiated by a process on a system. Attackers can abuse that feature to establish a reverse shell or persistence on a machine. ' references: - https://ipfyx.fr/post/visual-studio-code-tunnel/ - https://badoption.eu/blog/2023/01/31/code_c2.html - https://cydefops.com/vscode-data-exfiltration author: Kamran Saifullah date: 2023-11-20 tags: - attack.exfiltration - attack.command-and-control - attack.t1567 - attack.t1572 logsource: category: network_connection product: windows detection: selection: Initiated: 'true' DestinationHostname|endswith: .tunnels.api.visualstudio.com condition: selection falsepositives: - Legitimate use of Visual Studio Code tunnel will also trigger this. level: medium