RPC (Remote Procedure Call) to the Internet

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Detects network events that may indicate the use of RPC traffic to the Internet. RPC is commonly used by system administrators to remotely control a system for maintenance or to use shared resources. It should almost never be directly exposed to the Internet, as it is frequently targeted and exploited by threat actors as an initial access or back-door vector.

Rule type: query

Rule indices:

  • filebeat-*
  • packetbeat-*
  • logs-endpoint.events.*

Severity: high

Risk score: 73

Runs every: 5 minutes

Searches indices from: now-6m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Host
  • Network
  • Threat Detection
  • Initial Access

Version: 5 (version history)

Added (Elastic Stack release): 7.6.0

Last modified (Elastic Stack release): 7.10.0

Rule authors: Elastic

Rule license: Elastic License

Rule query

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event.category:(network or network_traffic) and network.transport:tcp
and (destination.port:135 or event.dataset:zeek.dce_rpc) and
source.ip:(10.0.0.0/8 or 172.16.0.0/12 or 192.168.0.0/16) and not
destination.ip:(10.0.0.0/8 or 127.0.0.0/8 or 172.16.0.0/12 or
192.168.0.0/16 or "::1")

Threat mapping

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Framework: MITRE ATT&CKTM

Rule version history

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Version 5 (7.10.0 release)
  • Formatting only
Version 4 (7.9.0 release)
  • Updated query, changed from:

    network.transport:tcp and destination.port:135 and
    source.ip:(10.0.0.0/8 or 172.16.0.0/12 or 192.168.0.0/16) and not
    destination.ip:(10.0.0.0/8 or 127.0.0.0/8 or 172.16.0.0/12 or
    192.168.0.0/16 or "::1")
Version 3 (7.7.0 release)
  • Updated query, changed from:

    network.transport: tcp and destination.port: 135 and (
    network.direction: outbound or ( source.ip: (10.0.0.0/8 or
    172.16.0.0/12 or 192.168.0.0/16) and not destination.ip: (10.0.0.0/8
    or 172.16.0.0/12 or 192.168.0.0/16) ) )
Version 2 (7.6.1 release)
  • Removed auditbeat-*, packetbeat-*, and winlogbeat-* from the rule indices.