Detection rules › Sigma
Suspicious Child Process Of Wermgr.EXE
Detects suspicious Windows Error Reporting manager (wermgr.exe) child process
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Privilege Escalation | T1055 Process Injection |
| Stealth | T1036 Masquerading, T1055 Process Injection |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
title: Suspicious Child Process Of Wermgr.EXE
id: 396f6630-f3ac-44e3-bfc8-1b161bc00c4e
related:
- id: 5394fcc7-aeb2-43b5-9a09-cac9fc5edcd5
type: similar
status: test
description: Detects suspicious Windows Error Reporting manager (wermgr.exe) child process
references:
- https://www.trendmicro.com/en_us/research/22/j/black-basta-infiltrates-networks-via-qakbot-brute-ratel-and-coba.html
- https://www.echotrail.io/insights/search/wermgr.exe
- https://github.com/binderlabs/DirCreate2System
author: Florian Roth (Nextron Systems)
date: 2022-10-14
modified: 2024-08-29
tags:
- attack.privilege-escalation
- attack.stealth
- attack.t1055
- attack.t1036
logsource:
category: process_creation
product: windows
detection:
selection:
ParentImage|endswith: '\wermgr.exe'
Image|endswith:
- '\cmd.exe'
- '\cscript.exe'
- '\ipconfig.exe'
- '\mshta.exe'
- '\net.exe'
- '\net1.exe'
- '\netstat.exe'
- '\nslookup.exe'
- '\powershell_ise.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\systeminfo.exe'
- '\whoami.exe'
- '\wscript.exe'
filter_main_rundll32:
Image|endswith: '\rundll32.exe'
CommandLine|contains|all:
- 'C:\Windows\system32\WerConCpl.dll'
- 'LaunchErcApp '
CommandLine|contains:
- '-queuereporting'
- '-responsepester'
condition: selection and not 1 of filter_main_*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_main_*Stage 1: selection
selection:
ParentImage|endswith: '\wermgr.exe'
Image|endswith:
- '\cmd.exe'
- '\cscript.exe'
- '\ipconfig.exe'
- '\mshta.exe'
- '\net.exe'
- '\net1.exe'
- '\netstat.exe'
- '\nslookup.exe'
- '\powershell_ise.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\systeminfo.exe'
- '\whoami.exe'
- '\wscript.exe'
Stage 2: not filter_main_rundll32
filter_main_rundll32:
Image|endswith: '\rundll32.exe'
CommandLine|contains|all:
- 'C:\Windows\system32\WerConCpl.dll'
- 'LaunchErcApp '
CommandLine|contains:
- '-queuereporting'
- '-responsepester'
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
CommandLine | match | -queuereporting |
CommandLine | match | -responsepester |
CommandLine | match | C:\Windows\system32\WerConCpl.dll |
CommandLine | match | LaunchErcApp |
Image | ends_with | \rundll32.exe |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
Image | ends_with |
|
ParentImage | ends_with |
|