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Killing a Process

For the policies that support kill responses, specify responseAction: kill.

A kill response action is performed by sending the SIGKILL signal to a process. This causes the process to exit immediately. It does not wait until the process has exited. This does not kill any other processes the target process may have started.

The following example demonstrates this applied to a program:

Enforced Wget Blocklist:
  policy: program
  responseAction: kill
  alertMessage: Unauthorized execution of wget
  comments: This policy detects and kills instances of wget running
  priority: High
  enabled: true
  rules:
  - match programName == "/usr/bin/wget"
  - default ignore

Kill responses can fail. For example, the process in question may no longer be running by the time the signal is sent to it. The following JSON is a truncated example alert for this configuration in a case where the process could not be killed:

"notifications": [
    {
      "timestamp": "2019-04-17T01:58:30.272044949-04:00",
      "name": "Enforced Wget Blocklist",
      "uuid": "25fc84c4-be3f-4159-a55e-1c31f85a29cb",
      "message": "The program \"/usr/bin/wget\" was executed, which violated the \"Enforced Wget Blocklist\" Program Policy. The stop response action was not successful.",
      "message_fields": {}
    },
    {
      "timestamp": "2019-04-17T01:58:30.272044949-04:00",
      "name": "Enforced Wget Blocklist",
      "uuid": "25fc84c4-be3f-4159-a55e-1c31f85a29cb",
      "message": "unable to stop process 2745: no such process",
      "message_fields": {
        "action_type": "stop",
        "action_target_type": "process",
        "action_result": "not successful",
        "action_result_details": "no such process"
      }
    }
  ],