Potential Windows Error Manager Masquerading

Identifies suspicious instances of the Windows Error Reporting process (WerFault.exe or Wermgr.exe) with matching command-line and process executable values performing outgoing network connections. This may be indicative of a masquerading attempt to evade suspicious child process behavior detections.

Rule type: eql

Rule indices:

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

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

Elastic
Host
Windows
Threat Detection
Defense Evasion

Version: 4

Rule authors:

Elastic

Rule license: Elastic License v2

Rule query

edit

sequence by host.id, process.entity_id with maxspan = 5s
  [process where event.type:"start" and process.name : ("wermgr.exe", "WerFault.exe") and process.args_count == 1]
  [network where process.name : ("wermgr.exe", "WerFault.exe") and network.protocol != "dns" and
    network.direction : ("outgoing", "egress") and destination.ip !="::1" and destination.ip !="127.0.0.1"
  ]

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Masquerading
- ID: T1036
- Reference URL: https://attack.mitre.org/techniques/T1036/

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