splApache-2.0from splunk/security_content

Network Connection Discovery With Arp

The following analytic detects the execution of `arp.exe` with the `-a` flag, which is used to list network connections on a compromised system. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, command-line executions, and related telemetry. Monitoring this activity is significant because both Red Teams and adversaries use `arp.exe` for situational awareness and Active Directory discovery. If confirmed malicious, this activity could allow attackers to map the network, identify active devices, and plan further lateral movement or attacks.

Quality

FP risk

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Forks

Views

Rule sourcedetections/endpoint/network_connection_discovery_with_arp.yml

| tstats `security_content_summariesonly`
  count min(_time) as firstTime
        max(_time) as lastTime

FROM datamodel=Endpoint.Processes WHERE

(
    Processes.process_name="arp.exe"
    OR
    Processes.process_original_file_name="arp.exe"
)
Processes.process IN (
    "* -a*",
    "* -g *",
    "* /a *",
    "* /g *"
)
BY Processes.action Processes.dest Processes.original_file_name
   Processes.parent_process Processes.parent_process_exec
   Processes.parent_process_guid Processes.parent_process_id
   Processes.parent_process_name Processes.parent_process_path
   Processes.process Processes.process_exec Processes.process_guid
   Processes.process_hash Processes.process_id Processes.process_integrity_level
   Processes.process_name Processes.process_path Processes.user
   Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `network_connection_discovery_with_arp_filter`