SigmaHQ/rules/windows/sysmon/sysmon_minidumwritedump_lsass.yml

title: Dumping Lsass.exe Memory with MiniDumpWriteDump API
id: dd5ab153-beaa-4315-9647-65abc5f71541
status: experimental
description: Detects the use of MiniDumpWriteDump API for dumping lsass.exe memory in a stealth way. Tools like ProcessHacker and some attacker tradecract use this
    API found in dbghelp.dll or dbgcore.dll. As an example, SilentTrynity C2 Framework has a module that leverages this API to dump the contents of Lsass.exe and
    transfer it over the network back to the attacker's machine.
date: 27/10/2019
modified: 2019/11/13
author: Perez Diego (@darkquassar), oscd.community
references:
    - https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/nf-minidumpapiset-minidumpwritedump
    - https://www.pinvoke.net/default.aspx/dbghelp/MiniDumpWriteDump.html
    - https://medium.com/@fsx30/bypass-edrs-memory-protection-introduction-to-hooking-2efb21acffd6
tags:
    - attack.credential_access
    - attack.t1003
logsource:
    product: windows
    service: sysmon
detection:
    signedprocess:
        EventID: 7
        ImageLoaded|endswith:
            - '\dbghelp.dll'
            - '\dbgcore.dll'
        Image|endswith: 
            - '\msbuild.exe'
            - '\cmd.exe'
            - '\svchost.exe'
            - '\rundll32.exe'
            - '\powershell.exe'
            - '\word.exe'
            - '\excel.exe'
            - '\powerpnt.exe'
            - '\outlook.exe'
            - '\monitoringhost.exe'
            - '\wmic.exe'
            - '\msiexec.exe'
            - '\bash.exe'
            - '\wscript.exe'
            - '\cscript.exe'
            - '\mshta.exe'
            - '\regsvr32.exe'
            - '\schtasks.exe'
            - '\dnx.exe'
            - '\regsvcs.exe'
            - '\sc.exe'
            - '\scriptrunner.exe'
    unsignedprocess:
        EventID: 7
        ImageLoaded|endswith:
            - '\dbghelp.dll'
            - '\dbgcore.dll'
        Signed: "FALSE"
    filter:
        Image|contains: 'Visual Studio'
    condition: (signedprocess AND NOT filter) OR (unsignedprocess AND NOT filter)
fields:
    - ComputerName
    - User
    - Image
    - ImageLoaded
falsepositives:
    - Penetration tests
level: critical