Unusual Network Activity from a Windows System Binary

Identifies network activity from unexpected system applications. This may indicate adversarial activity as these applications are often leveraged by adversaries to execute code and evade detection.

Rule type: eql

Rule indices:

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

Severity: medium

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: 2 (version history)

Added (Elastic Stack release): 7.10.0

Last modified (Elastic Stack release): 7.12.0

Rule authors: Elastic

Rule license: Elastic License v2

Rule query

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sequence by process.entity_id with maxspan=5m [process where
event.type in ("start", "process_started") and /* known
applocker bypasses */ (process.name : "bginfo.exe" or
process.name : "cdb.exe" or process.name : "control.exe" or
process.name : "cmstp.exe" or process.name : "csi.exe" or
process.name : "dnx.exe" or process.name : "fsi.exe" or
process.name : "ieexec.exe" or process.name : "iexpress.exe" or
process.name : "installutil.exe" or process.name :
"Microsoft.Workflow.Compiler.exe" or process.name :
"MSBuild.exe" or process.name : "msdt.exe" or process.name
: "mshta.exe" or process.name : "msiexec.exe" or
process.name : "msxsl.exe" or process.name : "odbcconf.exe" or
process.name : "rcsi.exe" or process.name : "regsvr32.exe" or
process.name : "xwizard.exe")] [network where (process.name :
"bginfo.exe" or process.name : "cdb.exe" or process.name :
"control.exe" or process.name : "cmstp.exe" or
process.name : "csi.exe" or process.name : "dnx.exe" or
process.name : "fsi.exe" or process.name : "ieexec.exe" or
process.name : "iexpress.exe" or process.name :
"installutil.exe" or process.name :
"Microsoft.Workflow.Compiler.exe" or process.name :
"MSBuild.exe" or process.name : "msdt.exe" or process.name
: "mshta.exe" or process.name : "msiexec.exe" or
process.name : "msxsl.exe" or process.name : "odbcconf.exe" or
process.name : "rcsi.exe" or process.name : "regsvr32.exe" or
process.name : "xwizard.exe")]

Threat mapping

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Framework: MITRE ATT&CK^TM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Trusted Developer Utilities Proxy Execution
- ID: T1127
- Reference URL: https://attack.mitre.org/techniques/T1127/

Rule version history

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Version 2 (7.12.0 release)

Formatting only

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