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Description

This search detects attempts to run exploits for the Zerologon CVE-2020-1472 vulnerability via Zeek RPC

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel:
  • Last Updated: 2020-09-15
  • Author: Shannon Davis, Splunk
  • ID: bf7a06ec-f703-11ea-adc1-0242ac120002

ATT&CK

ID Technique Tactic
T1190 Exploit Public-Facing Application Initial Access
`zeek_rpc` operation IN (NetrServerPasswordSet2,NetrServerReqChallenge,NetrServerAuthenticate3) 
| bin span=5m _time 
| stats values(operation) dc(operation) as opscount count(eval(operation=="NetrServerReqChallenge")) as challenge count(eval(operation=="NetrServerAuthenticate3")) as authcount count(eval(operation=="NetrServerPasswordSet2")) as passcount count as totalcount by _time,src_ip,dest_ip 
| search opscount=3 authcount>4 passcount>0 
| search `detect_zerologon_via_zeek_filter`

Associated Analytic Story

How To Implement

You must be ingesting Zeek DCE-RPC data into Splunk. Zeek data should also be getting ingested in JSON format. We are detecting when all three RPC operations (NetrServerReqChallenge, NetrServerAuthenticate3, NetrServerPasswordSet2) are splunk_security_essentials_app via bro:rpc:json. These three operations are then correlated on the Zeek UID field.

Required field

  • _time
  • operation

Kill Chain Phase

  • Exploitation

Known False Positives

unknown

CVE

ID Summary CVSS
CVE-2020-1472 An elevation of privilege vulnerability exists when an attacker establishes a vulnerable Netlogon secure channel connection to a domain controller, using the Netlogon Remote Protocol (MS-NRPC), aka 'Netlogon Elevation of Privilege Vulnerability'. 9.3

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

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