Suspicious Netcat Execution

[rule]
description = """
This rule detects the usage of netcat to connect to a remote host. This behavior may be indicative of a reverse shell
connection being established.
"""
id = "a60859af-bd25-449d-bdb3-e71cb1725f58"
license = "Elastic License v2"
name = "Suspicious Netcat Execution"
os_list = ["linux"]
version = "1.0.2"

query = '''
process where event.type == "start" and event.action == "exec" and
process.name in ("nc", "ncat", "netcat", "netcat.openbsd", "netcat.traditional", "nc.openbsd", "nc.traditional") and
process.args regex "[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}" and
process.args_count >= 3 and
not (
  process.args like ("127.0.0.1", "127.0.0.01", "0.0.0.0", "::1", "-*z*", "--help", "8.8.8.8") or
  process.args regex """10\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}""" or
  process.args regex """192\.168\.[0-9]{1,3}\.[0-9]{1,3}""" or
  process.args regex """172\.(1[6-9]|2[0-9]|3[0-1])\.[0-9]{1,3}\.[0-9]{1,3}""" or
  (process.parent.executable == "/usr/sbin/sshd" and process.args == "22")
)
'''

min_endpoint_version = "7.15.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 0

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"
[[threat.technique.subtechnique]]
id = "T1059.004"
name = "Unix Shell"
reference = "https://attack.mitre.org/techniques/T1059/004/"



[threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1071"
name = "Application Layer Protocol"
reference = "https://attack.mitre.org/techniques/T1071/"


[threat.tactic]
id = "TA0011"
name = "Command and Control"
reference = "https://attack.mitre.org/tactics/TA0011/"

[internal]
min_endpoint_version = "7.15.0"