mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
research bot
54 lines
2.5 KiB
YAML
54 lines
2.5 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
|
|
type: batch
|
|
datamodel:
|
|
- Endpoint
|
|
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.
|
|
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
|
|
as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name=wsmprovhost.exe
|
|
Processes.process_name IN ("cmd.exe","sh.exe","bash.exe","powershell.exe","pwsh.exe","schtasks.exe","certutil.exe","whoami.exe","bitsadmin.exe","scp.exe")
|
|
by Processes.dest Processes.user Processes.parent_process Processes.process_name
|
|
Processes.process Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)`
|
|
| `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `winrm_spawning_a_process_filter`'
|
|
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/master/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
|
|
dataset: []
|
|
kill_chain_phases:
|
|
- Exploitation
|
|
- Privilege Escalation
|
|
- Denial of Service
|
|
mitre_attack_id:
|
|
- T1190
|
|
product:
|
|
- Splunk Enterprise
|
|
- Splunk Enterprise Security
|
|
- Splunk Cloud
|
|
required_fields:
|
|
- _time
|
|
- Processes.dest
|
|
- Processes.user
|
|
- Processes.parent_process
|
|
- Processes.process_name
|
|
- Processes.process
|
|
- Processes.process_id
|
|
- Processes.parent_process_id
|
|
security_domain: endpoint
|