TCP Port 8000 Activity to the Internet

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TCP Port 8000 is commonly used for development environments of web server software. It generally should not be exposed directly to the Internet. If you are running software like this on the Internet, you should consider placing it behind a reverse proxy.

Rule type: query

Rule indices:

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

Severity: low

Risk score: 21

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
  • Command and Control

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

Potential false positives

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Because this port is in the ephemeral range, this rule may false under certain conditions, such as when a NATed web server replies to a client which has used a port in the range by coincidence. In this case, such servers can be excluded. Some applications may use this port but this is very uncommon and usually appears in local traffic using private IPs, which this rule does not match. Some cloud environments, particularly development environments, may use this port when VPNs or direct connects are not in use and cloud instances are accessed across the Internet.

Rule query

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event.category:(network or network_traffic) and network.transport:tcp
and destination.port:8000 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:8000 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: 8000 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.