mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
P4T12ICK
66 lines
2.1 KiB
YAML
66 lines
2.1 KiB
YAML
name: WinRM Spawning a Process
|
|
id: a081836a-ba4d-11eb-8593-acde48001122
|
|
version: 1
|
|
date: '2021-05-21'
|
|
author: Drew Church, Michael Haag, Splunk
|
|
status: experimental
|
|
type: TTP
|
|
description: The following analytic identifies suspicious processes spawning from
|
|
WinRM (wsmprovhost.exe). This analytic is related to potential exploitation of CVE-2021-31166.
|
|
which is a kernel-mode device driver http.sys vulnerability. Current proof of concept
|
|
code will blue-screen the operating system. However, http.sys used by many different
|
|
Windows processes, including WinRM. In this case, identifying suspicious process
|
|
create (child processes) from `wsmprovhost.exe` is what this analytic is identifying.
|
|
data_source:
|
|
- Sysmon Event ID 1
|
|
search:
|
|
selection1:
|
|
Image|endswith:
|
|
- cmd.exe
|
|
- sh.exe
|
|
- bash.exe
|
|
- powershell.exe
|
|
- pwsh.exe
|
|
- schtasks.exe
|
|
- certutil.exe
|
|
- whoami.exe
|
|
- bitsadmin.exe
|
|
- scp.exe
|
|
ParentImage: wsmprovhost.exe
|
|
condition: selection1
|
|
how_to_implement: To successfully implement this search you need to be ingesting information
|
|
on process that include the name of the process responsible for the changes from
|
|
your endpoints into the `Endpoint` datamodel in the `Processes` node.
|
|
known_false_positives: Unknown. Add new processes or filter as needed. It is possible
|
|
system management software may spawn processes from `wsmprovhost.exe`.
|
|
references:
|
|
- https://github.com/SigmaHQ/sigma/blob/9b7fb0c0f3af2e53ed483e29e0d0f88ccf1c08ca/rules/windows/process_access/win_susp_shell_spawn_from_winrm.yml
|
|
- https://www.zerodayinitiative.com/blog/2021/5/17/cve-2021-31166-a-wormable-code-execution-bug-in-httpsys
|
|
- https://github.com/0vercl0k/CVE-2021-31166/blob/main/cve-2021-31166.py
|
|
tags:
|
|
analytic_story:
|
|
- Unusual Processes
|
|
asset_type: Endpoint
|
|
confidence: 50
|
|
cve:
|
|
- CVE-2021-31166
|
|
impact: 50
|
|
message: tbd
|
|
mitre_attack_id:
|
|
- T1190
|
|
observable:
|
|
- name: user
|
|
type: User
|
|
role:
|
|
- Victim
|
|
- name: dest
|
|
type: Hostname
|
|
role:
|
|
- Victim
|
|
product:
|
|
- Splunk Enterprise
|
|
- Splunk Enterprise Security
|
|
- Splunk Cloud
|
|
risk_score: 25
|
|
security_domain: endpoint
|