mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
70 lines
2.6 KiB
YAML
70 lines
2.6 KiB
YAML
name: Spoolsv Spawning Rundll32
|
|
id: 15d905f6-da6b-11eb-ab82-acde48001122
|
|
version: 2
|
|
date: '2021-07-01'
|
|
author: Mauricio Velazco, Michael Haag, Splunk
|
|
status: production
|
|
type: TTP
|
|
description: The following analytic identifies a suspicious child process, `rundll32.exe`,
|
|
with no command-line arguments being spawned from `spoolsv.exe`. This was identified
|
|
during our testing of CVE-2021-34527 previously (CVE-2021-1675) or PrintNightmare.
|
|
Typically, this is not normal behavior for `spoolsv.exe` to spawn a process. During
|
|
triage, isolate the endpoint and review for source of exploitation. Capture any
|
|
additional file modification events.
|
|
data_source:
|
|
- Sysmon Event ID 1
|
|
search:
|
|
selection1:
|
|
ParentImage: spoolsv.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. In addition,
|
|
confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
|
|
endpoint product.
|
|
known_false_positives: Limited false positives have been identified. There are limited
|
|
instances where `rundll32.exe` may be spawned by a legitimate print driver.
|
|
references:
|
|
- https://www.truesec.com/hub/blog/fix-for-printnightmare-cve-2021-1675-exploit-to-keep-your-print-servers-running-while-a-patch-is-not-available
|
|
- https://www.truesec.com/hub/blog/exploitable-critical-rce-vulnerability-allows-regular-users-to-fully-compromise-active-directory-printnightmare-cve-2021-1675
|
|
- https://www.reddit.com/r/msp/comments/ob6y02/critical_vulnerability_printnightmare_exposes
|
|
tags:
|
|
analytic_story:
|
|
- PrintNightmare CVE-2021-34527
|
|
asset_type: Endpoint
|
|
confidence: 90
|
|
cve:
|
|
- CVE-2021-34527
|
|
impact: 80
|
|
message: $parent_process$ has spawned $process_name$ on endpoint $ComputerName$.
|
|
This behavior is suspicious and related to PrintNightmare.
|
|
mitre_attack_id:
|
|
- T1547.012
|
|
- T1547
|
|
observable:
|
|
- name: dest
|
|
type: Endpoint
|
|
role:
|
|
- Victim
|
|
- name: parent_process_id
|
|
type: Process
|
|
role:
|
|
- Parent Process
|
|
- Attacker
|
|
- name: process_id
|
|
type: Process
|
|
role:
|
|
- Child Process
|
|
product:
|
|
- Splunk Enterprise
|
|
- Splunk Enterprise Security
|
|
- Splunk Cloud
|
|
risk_score: 72
|
|
security_domain: endpoint
|
|
tests:
|
|
- name: True Positive Test
|
|
attack_data:
|
|
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1547.012/printnightmare/windows-sysmon.log
|
|
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
|
|
sourcetype: xmlwineventlog
|