mirror of https://github.com/infosecn1nja/HELK.git
128 lines
3.0 KiB
Plaintext
128 lines
3.0 KiB
Plaintext
{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"# Certutil Encode\n",
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"Detects suspicious a certutil command that used to encode files, which is sometimes used for data exfiltration"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Rule Content\n",
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"```\n",
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"- title: Certutil Encode\n",
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" id: e62a9f0c-ca1e-46b2-85d5-a6da77f86d1a\n",
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" status: experimental\n",
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" description: Detects suspicious a certutil command that used to encode files, which\n",
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" is sometimes used for data exfiltration\n",
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" references:\n",
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" - https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/certutil\n",
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" - https://unit42.paloaltonetworks.com/new-babyshark-malware-targets-u-s-national-security-think-tanks/\n",
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" author: Florian Roth\n",
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" date: 2019/02/24\n",
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" logsource:\n",
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" category: process_creation\n",
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" product: windows\n",
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" service: null\n",
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" detection:\n",
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" selection:\n",
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" CommandLine:\n",
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" - certutil -f -encode *\n",
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" - certutil.exe -f -encode *\n",
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" - certutil -encode -f *\n",
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" - certutil.exe -encode -f *\n",
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" condition: selection\n",
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" falsepositives:\n",
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" - unknown\n",
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" level: medium\n",
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"\n",
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"```"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Querying Elasticsearch"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"### Import Libraries"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"from elasticsearch import Elasticsearch\n",
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"from elasticsearch_dsl import Search\n",
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"import pandas as pd"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"### Initialize Elasticsearch client"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"es = Elasticsearch(['http://helk-elasticsearch:9200'])\n",
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"searchContext = Search(using=es, index='logs-*', doc_type='doc')"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"### Run Elasticsearch Query"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"s = searchContext.query('query_string', query='process_command_line.keyword:(certutil\\ \\-f\\ \\-encode\\ * OR certutil.exe\\ \\-f\\ \\-encode\\ * OR certutil\\ \\-encode\\ \\-f\\ * OR certutil.exe\\ \\-encode\\ \\-f\\ *)')\n",
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"response = s.execute()\n",
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"if response.success():\n",
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" df = pd.DataFrame((d.to_dict() for d in s.scan()))"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"### Show Results"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"df.head()"
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]
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}
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],
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"metadata": {},
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"nbformat": 4,
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"nbformat_minor": 4
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}
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