Detectionhighexperimental
HackTool - WSASS Execution
Detects execution of WSASS, a tool used to dump LSASS memory on Windows systems by leveraging WER's (Windows Error Reporting) WerFaultSecure.EXE to bypass PPL (Protected Process Light) protections.
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Launch
Swachchhanda Shrawan Poudel (Nextron Systems)Created Sun Nov 23Updated Fri Jan 09589ac73f-8e12-409c-964e-31a2f5775ae2windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation
Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.
Detection Logic
Detection Logic3 selectors
detection:
selection_img:
Image|endswith: '\wsass.exe'
selection_hash:
Hashes|contains: 'IMPHASH=32F5095C9BBDCACF28FD4060EB4DFC42'
selection_cli:
# change to |re|i after Sigma v2.0 release
# plain string without quotation marks as it has to match for both ' and "
CommandLine|re: (?i)\.exe[\"\']?\s+[^\"]{0,64}werfaultsecure\.exe[\"\']?\s+\d{2,10} # wsass.exe "path to werfaultsecure" lsass_pid
condition: 1 of selection_*False Positives
Unlikely
False positives are unlikely for most environments. High confidence detection.
MITRE ATT&CK
Tactics
Sub-techniques
Rule Metadata
Rule ID
589ac73f-8e12-409c-964e-31a2f5775ae2
Status
experimental
Level
high
Type
Detection
Created
Sun Nov 23
Modified
Fri Jan 09
Path
rules/windows/process_creation/proc_creation_win_hktl_wsass.yml
Raw Tags
attack.credential-accessattack.t1003.001