Detection rules › Sigma

SystemNightmare by GentilKiwi - New external device added (CVE-2021-1675 / CVE-2021-34527)

Status
experimental
Severity
high
Log source
product windows, service security
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker exploit the PrintNightmare vulnerability by abusing the Windows print spooler using the service exposed by Gentilkiwi

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: SystemNightmare by GentilKiwi - New external device added (CVE-2021-1675 / CVE-2021-34527)
description: Detects scenarios where an attacker exploit the PrintNightmare vulnerability by abusing the Windows print spooler using the service exposed by Gentilkiwi
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0004-Privilege%20Escalation/T1574-DLL%20side-loading
- https://github.com/GossiTheDog/SystemNightmare
- https://github.com/outflanknl/PrintNightmare
- https://github.com/cube0x0/CVE-2021-1675
- https://www.theregister.com/2021/09/21/microsoft_printnightmare/
- https://www.exabeam.com/information-security/detecting-the-printnightmare-cve-2021-1675-34527-vulnerability-using-exabeam/
tags:
- attack.privilege_escalation
- attack.t1574.002
- attack.t1547.010
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection: # net use \\printnightmare.gentilkiwi.com\ipc$ /user:gentilguest password
  selection:
    EventID: 6416
    DeviceDescription|contains: # original: '\\printnightmare.gentilkiwi.com\Kiwi Legit Printer'
      - printnightmare
      - gentil
      - kiwi
  condition: selection
falsepositives:
- pentest
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  EventID: 6416
  DeviceDescription|contains:
    - printnightmare
    - gentil
    - kiwi

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.

FieldKindValues
DeviceDescriptionmatch
  • gentil
  • kiwi
  • printnightmare