Mounting Hidden or WebDav Remote Shares

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Identifies the use of net.exe to mount a WebDav or hidden remote share. This may indicate lateral movement or preparation for data exfiltration.

Rule type: eql

Rule indices:

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

Severity: medium

Risk score: 21

Runs every: 5m

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

Maximum alerts per execution: 100

References: None

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Lateral Movement

Version: 4

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guide

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## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.

Rule query

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process where event.type in ("start", "process_started") and
 ((process.name : "net.exe" or process.pe.original_file_name == "net.exe") or ((process.name : "net1.exe" or process.pe.original_file_name == "net1.exe") and
 not process.parent.name : "net.exe")) and
 process.args : "use" and
 /* including hidden and webdav based online shares such as onedrive  */
 process.args : ("\\\\*\\*$*", "\\\\*@SSL\\*", "http*") and
 /* excluding shares deletion operation */
 not process.args : "/d*"

Framework: MITRE ATT&CKTM