Windows WerFault LSASS Memory Dump File Creation
Flags WerFault dump creation where the dump filename suggests it contains LSASS memory.
FreeReviewedSigma · High · v2
- Product
- windows
- Category
- file_event
- Author
- Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
- Published
- 2022-06-27
- Updated
- 2026-07-31
ATT&CK techniques
Cred AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule identifies executions of WerFault.exe that create dump files whose names contain references to lsass or lsass.exe. Dumping LSASS process memory can expose user credentials, making it a high-value step in credential access. It relies on Windows file creation telemetry that records the process image path and the target dump filename.
Reporting behind it
Changelog
v2- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
windows-werfault-creates-dump-files-referencing-lsass-process-memory-c3e76af5
title: Windows WerFault LSASS Memory Dump File Creation
id: 7ae989b0-b6f6-4270-9799-9099a7d3724e
status: test
description: This rule identifies executions of WerFault.exe that create dump files whose names contain references to lsass or lsass.exe. Dumping LSASS process memory can expose user credentials, making it a high-value step in credential access. It relies on Windows file creation telemetry that records the process image path and the target dump filename.
references:
- https://github.com/helpsystems/nanodump
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/file/file_event/file_event_win_lsass_werfault_dump.yml
author: Florian Roth (Nextron Systems), Huntrule Team
date: 2022-06-27
tags:
- attack.credential-access
- attack.t1003.001
logsource:
product: windows
category: file_event
detection:
selection:
Image: C:\WINDOWS\system32\WerFault.exe
TargetFilename|contains:
- \lsass
- lsass.exe
condition: selection
falsepositives:
- Unknown
level: high
license: DRL-1.1
related:
- id: c3e76af5-4ce0-4a14-9c9a-25ceb8fda182
type: derived