Command Prompt Network Connectionedit

Identifies cmd.exe making a network connection. Adversaries could abuse cmd.exe to download or execute malware from a remote URL.

Rule type: eql

Rule indices:

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

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

References:

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Execution

Version: 7 (version history)

Added (Elastic Stack release): 7.6.0

Last modified (Elastic Stack release): 7.14.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positivesedit

Administrators may use the command prompt for regular administrative tasks. It’s important to baseline your environment for network connections being made from the command prompt to determine any abnormal use of this tool.

Rule queryedit

sequence by process.entity_id [process where process.name :
"cmd.exe" and event.type == "start"] [network where process.name :
"cmd.exe" and not cidrmatch(destination.ip, "10.0.0.0/8",
"127.0.0.0/8", "169.254.0.0/16", "172.16.0.0/12", "192.0.0.0/24",
"192.0.0.0/29", "192.0.0.8/32", "192.0.0.9/32", "192.0.0.10/32",
"192.0.0.170/32", "192.0.0.171/32",
"192.0.2.0/24", "192.31.196.0/24", "192.52.193.0/24",
"192.168.0.0/16", "192.88.99.0/24", "224.0.0.0/4", "100.64.0.0/10",
"192.175.48.0/24", "198.18.0.0/15",
"198.51.100.0/24", "203.0.113.0/24", "240.0.0.0/4", "::1",
"FE80::/10", "FF00::/8")]

Threat mappingedit

Framework: MITRE ATT&CKTM

Rule version historyedit

Version 7 (7.14.0 release)
  • Updated query, changed from:

    sequence by process.entity_id [process where process.name :
    "cmd.exe" and event.type == "start"] [network where process.name :
    "cmd.exe" and not cidrmatch(destination.ip, "10.0.0.0/8",
    "172.16.0.0/12", "192.168.0.0/16")]
Version 6 (7.12.0 release)
  • Formatting only
Version 5 (7.10.0 release)
  • Updated query, changed from:

    event.category:network and event.type:connection and
    process.name:cmd.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:cmd.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:cmd.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