Detection rules › Sigma
Potential Credential Dumping Activity Via LSASS
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.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Credential Access |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 10: ProcessAccess |
Rule body
title: Potential Credential Dumping Activity Via LSASS
id: 5ef9853e-4d0e-4a70-846f-a9ca37d876da
status: test
description: |
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://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: Samir Bousseaden, Michael Haag
date: 2019-04-03
modified: 2026-06-29
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' # Too many false positives
# - '0x01000' # Too many false positives
# - '0x1010' # Too many false positives
# - '0x1400' # Too many false positives
# - '0x1410' # Too many false positives
# - '0x40' # Too many false positives
CallTrace|contains:
- 'dbgcore.dll'
- 'dbghelp.dll'
- 'kernel32.dll'
- 'kernelbase.dll'
- 'ntdll.dll'
filter_main_system_user:
SourceUser|contains: # Covers many language settings
- '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
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_main_* and not 1 of filter_optional_*Stage 1: selection
selection:
TargetImage|endswith: '\lsass.exe'
GrantedAccess|contains:
- '0x1038'
- '0x1438'
- '0x143a'
- '0x1fffff'
CallTrace|contains:
- 'dbgcore.dll'
- 'dbghelp.dll'
- 'kernel32.dll'
- 'kernelbase.dll'
- 'ntdll.dll'
Stage 2: not filter_main_system_user
filter_main_system_user:
SourceUser|contains:
- 'AUTHORI'
- 'AUTORI'
Stage 3: not filter_optional_*
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'
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
SourceUser | match | AUTHORI | excludes:SourceUser field:"SourceUser" value:"AUTHORI" |
SourceUser | match | AUTORI | excludes:SourceUser field:"SourceUser" value:"AUTORI" |
CallTrace | match | :\Windows\Temp\asgard2-agent\ | excludes:CallTrace field:"CallTrace" value:":\Windows\Temp\asgard2-agent\" |
CallTrace | match | \thor\thor64.exe+ | excludes:CallTrace field:"CallTrace" value:"\thor\thor64.exe+" |
CallTrace | match | |UNKNOWN( | excludes:CallTrace field:"CallTrace" value:"|UNKNOWN(" |
GrantedAccess | eq | 0x103800 | excludes:GrantedAccess field:"GrantedAccess" value:"0x103800" |
SourceImage | ends_with | :\Windows\Sysmon64.exe | excludes:SourceImage field:"SourceImage" value:":\Windows\Sysmon64.exe" |
SourceImage | ends_with | :\Windows\Sysmon64a.exe | excludes:SourceImage field:"SourceImage" value:":\Windows\Sysmon64a.exe" |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CallTrace | match |
| field:"CallTrace" kind:match |
GrantedAccess | match |
| field:"GrantedAccess" kind:match |
TargetImage | ends_with |
| field:"TargetImage" kind:ends_with value:"\lsass.exe" |