Network Connection via Signed Binary

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Binaries signed with trusted digital certificates can execute on Windows systems protected by digital signature validation. Adversaries may use these binaries to live off the land and execute malicious files that could bypass application allowlists and signature validation.

Rule type: eql

Rule indices:

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

Severity: low

Risk score: 21

Runs every: 5 minutes

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

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Defense Evasion

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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sequence by process.entity_id [process where (process.name :
"expand.exe" or process.name : "extrac.exe" or
process.name : "ieexec.exe" or process.name : "makecab.exe") and
event.type == "start"] [network where (process.name : "expand.exe"
or process.name : "extrac.exe" or process.name :
"ieexec.exe" or process.name : "makecab.exe") and not
cidrmatch(destination.ip, "10.0.0.0/8", "172.16.0.0/12",
"192.168.0.0/16")]

Threat mapping

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Framework: MITRE ATT&CKTM

Rule version history

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Version 5 (7.10.0 release)
  • Updated query, changed from:

    event.category:network and event.type:connection and
    process.name:(expand.exe or extrac.exe or ieexec.exe or makecab.exe)
    and not destination.ip:(10.0.0.0/8 or 172.16.0.0/12 or 192.168.0.0/16)
Version 4 (7.9.1 release)
  • Formatting only
Version 3 (7.9.0 release)
  • Updated query, changed from:

    process.name:(expand.exe or extrac.exe or ieexec.exe or makecab.exe)
    and event.action:"Network connection detected (rule: NetworkConnect)"
    and not destination.ip:(10.0.0.0/8 or 172.16.0.0/12 or 192.168.0.0/16)
Version 2 (7.7.0 release)
  • Updated query, changed from:

    (process.name:expand.exe or process.name:extrac.exe or
    process.name:ieexec.exe or process.name:makecab.exe) and
    event.action:"Network connection detected (rule: NetworkConnect)" and
    not destination.ip:10.0.0.0/8 and not destination.ip:172.16.0.0/12 and
    not destination.ip:192.168.0.0/16