Detectionhightest

Credential Dumping Attempt Via WerFault

Detects process LSASS memory dump using Mimikatz, NanoDump, Invoke-Mimikatz, Procdump or Taskmgr based on the CallTrace pointing to ntdll.dll, dbghelp.dll or dbgcore.dll for win10, server2016 and up.

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Launch
Florian Roth (Nextron Systems)Created Wed Jun 27Updated Wed Nov 29e5b33f7d-eb93-48b6-9851-09e1e610b6d7windows
Log Source
WindowsProcess Access
ProductWindows← raw: windows
CategoryProcess Access← raw: process_access

Events when a process opens a handle to another process, commonly used for credential dumping via LSASS.

Detection Logic
Detection Logic1 selector
detection:
    selection:
        SourceImage|endswith: '\WerFault.exe'
        TargetImage|endswith: '\lsass.exe'
        GrantedAccess: '0x1FFFFF'
    condition: selection
False Positives

Actual failures in lsass.exe that trigger a crash dump (unlikely)

Unknown cases in which WerFault accesses lsass.exe

Rule Metadata
Rule ID
e5b33f7d-eb93-48b6-9851-09e1e610b6d7
Status
test
Level
high
Type
Detection
Created
Wed Jun 27
Modified
Wed Nov 29
Path
rules/windows/process_access/proc_access_win_lsass_werfault.yml
Raw Tags
attack.credential-accessattack.t1003.001attack.s0002
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