Potential Local NTLM Relay via HTTP

Elastic Stack Serverless Security

Identifies attempt to coerce a local NTLM authentication via HTTP using the Windows Printer Spooler service as a target. An adversary may use this primitive in combination with other techniques to elevate privileges on a compromised system.

Rule type: eql

Rule indices:

• winlogbeat-*
• logs-endpoint.events.*
• logs-windows.*
• endgame-*

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://github.com/med0x2e/NTLMRelay2Self
• https://github.com/topotam/PetitPotam
• https://github.com/dirkjanm/krbrelayx/blob/master/printerbug.py

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Credential Access
• Elastic Endgame

Version: 102

Rule authors:

• Elastic

Rule license: Elastic License v2

process where event.type == "start" and
  process.name : "rundll32.exe" and

  /* Rundll32 WbeDav Client  */
  process.args : ("?:\\Windows\\System32\\davclnt.dll,DavSetCookie", "?:\\Windows\\SysWOW64\\davclnt.dll,DavSetCookie") and

  /* Access to named pipe via http */
  process.args : ("http*/print/pipe/*", "http*/pipe/spoolss", "http*/pipe/srvsvc")

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Credential Access
  • ID: TA0006
  • Reference URL: https://attack.mitre.org/tactics/TA0006/

• Technique:

  • Name: Exploitation for Credential Access
  • ID: T1212
  • Reference URL: https://attack.mitre.org/techniques/T1212/