{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Rundll32 Internet Connection\n",
    "Detects a rundll32 that communicates with public IP addresses"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Rule Content\n",
    "```\n",
    "- title: Rundll32 Internet Connection\n",
    "  id: cdc8da7d-c303-42f8-b08c-b4ab47230263\n",
    "  status: experimental\n",
    "  description: Detects a rundll32 that communicates with public IP addresses\n",
    "  references:\n",
    "  - https://www.hybrid-analysis.com/sample/759fb4c0091a78c5ee035715afe3084686a8493f39014aea72dae36869de9ff6?environmentId=100\n",
    "  author: Florian Roth\n",
    "  date: 2017/11/04\n",
    "  tags:\n",
    "  - attack.t1085\n",
    "  - attack.defense_evasion\n",
    "  - attack.execution\n",
    "  logsource:\n",
    "    product: windows\n",
    "    service: sysmon\n",
    "    category: null\n",
    "  detection:\n",
    "    selection:\n",
    "      EventID: 3\n",
    "      Image: '*\\rundll32.exe'\n",
    "      Initiated: 'true'\n",
    "    filter:\n",
    "      DestinationIp:\n",
    "      - 10.*\n",
    "      - 192.168.*\n",
    "      - 172.16.*\n",
    "      - 172.17.*\n",
    "      - 172.18.*\n",
    "      - 172.19.*\n",
    "      - 172.20.*\n",
    "      - 172.21.*\n",
    "      - 172.22.*\n",
    "      - 172.23.*\n",
    "      - 172.24.*\n",
    "      - 172.25.*\n",
    "      - 172.26.*\n",
    "      - 172.27.*\n",
    "      - 172.28.*\n",
    "      - 172.29.*\n",
    "      - 172.30.*\n",
    "      - 172.31.*\n",
    "      - 127.*\n",
    "    condition: selection and not filter\n",
    "  falsepositives:\n",
    "  - Communication to other corporate systems that use IP addresses from public address\n",
    "    spaces\n",
    "  level: medium\n",
    "\n",
    "```"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Querying Elasticsearch"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Import Libraries"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from elasticsearch import Elasticsearch\n",
    "from elasticsearch_dsl import Search\n",
    "import pandas as pd"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Initialize Elasticsearch client"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "es = Elasticsearch(['http://helk-elasticsearch:9200'])\n",
    "searchContext = Search(using=es, index='logs-endpoint-winevent-sysmon-*', doc_type='doc')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Run Elasticsearch Query"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "s = searchContext.query('query_string', query='((event_id:\"3\" AND process_path.keyword:*\\\\rundll32.exe AND network_initiated:\"true\") AND (NOT (dst_ip_addr.keyword:(10.* OR 192.168.* OR 172.16.* OR 172.17.* OR 172.18.* OR 172.19.* OR 172.20.* OR 172.21.* OR 172.22.* OR 172.23.* OR 172.24.* OR 172.25.* OR 172.26.* OR 172.27.* OR 172.28.* OR 172.29.* OR 172.30.* OR 172.31.* OR 127.*))))')\n",
    "response = s.execute()\n",
    "if response.success():\n",
    "    df = pd.DataFrame((d.to_dict() for d in s.scan()))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Show Results"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "df.head()"
   ]
  }
 ],
 "metadata": {},
 "nbformat": 4,
 "nbformat_minor": 4
}