Possible Credential Dumping Behavior Through LSASS (via process_access)

This rule detects process access requests to the LSASS process with specific call trace calls and access masks. This behaviour is expressed by many credential dumping tools such as Mimikatz, NanoDump, Invoke-Mimikatz, Procdump and even the Taskmgr dumping feature.

SigmamediumWindowsv1
sigma
title: Possible Credential Dumping Behavior Through LSASS (via process_access)
id: 07da14c3-df03-5df1-bb67-cea1347deaf0
status: stable
description: This rule detects process access requests to the LSASS process with specific call trace calls and access masks. This behaviour is expressed by many credential dumping tools such as Mimikatz, NanoDump, Invoke-Mimikatz, Procdump and even the Taskmgr dumping feature.
references:
    - https://attack.mitre.org/techniques/T1003/001/
    - https://web.archive.org/web/20230329170326/https://blog.menasec.net/2019/02/threat-hunting-21-procdump-or-taskmgr.html
    - https://web.archive.org/web/20230208123920/https://cyberwardog.blogspot.com/2017/03/chronicles-of-threat-hunter-hunting-for_22.html
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003.001/T1003.001.md
    - https://research.splunk.com/endpoint/windows_possible_credential_dumping/
author: Huntrule Team
date: 2026-04-14
tags:
    - attack.credential-access
    - attack.t1003.001
    - attack.s0002
logsource:
    category: process_access
    product: windows
detection:
    selection:
        TargetImage|endswith: '\lsass.exe'
        GrantedAccess|contains:
            - '0x1038'
            - '0x1438'
            - '0x143a'
            - '0x1fffff'
        CallTrace|contains:
            - 'dbgcore.dll'
            - 'dbghelp.dll'
            - 'kernel32.dll'
            - 'kernelbase.dll'
            - 'ntdll.dll'
    filter_main_system_user:
        SourceUser|contains:
            - 'AUTHORI'
            - 'AUTORI'
    filter_optional_thor:
        CallTrace|contains|all:
            - ':\Windows\Temp\asgard2-agent\'
            - '\thor\thor64.exe+'
            - '|UNKNOWN('
        GrantedAccess: '0x103800'
    filter_optional_sysmon:
        SourceImage|endswith:
            - ':\Windows\Sysmon64.exe'
            - ':\Windows\Sysmon64a.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.