Twitter Search to Cisco SecureX Threat Response Casebook [v1.1]

This is a sample script to search the Twitter hashtag #opendir for threat/malware related observables, check for Target Sightings and automatically add observables to Cisco Casebook. This enables Security Researchers and Threat Responders in a SOC to quickly see if the observables from #opendir have been seen in their environment (by leveraging SecureX Threat Response (SxTR)). The #opendir hashtag is used by many threat intelligence researchers to post their findings on new threats.

For more information on how to use SxTR, please review this link: https://visibility.amp.cisco.com/#/help/introduction.

Known issues

No known issues.

Release notes version 1.1

The "twitter" library is being used to reach the Twitter standard search API.
The "webexteamssdk" library is beinbg used to post send alerts.
The script also removes all clean observables from the case to stop false positives. Often legitimate websites are added in a tweet, but are not an observable associated directly with the malware campaign. This causes Target Sightings, without them being of much interest. Removing these from the investigation is also better for the performance of the script.
The script now also checks for Target Sightings. If there is a Sighting of a Target, the Webex Teams message and the Case description in Casebook will get a "HIGH PRIORITY" tag.
The Webex Teams message contains a direct investigate link to cross launch to SecureX threat response.

Overview

The script leverages the #opendir Twitter hashtag to find tweets related to new malware campaigns.
It will then check if this is the first time the script has run:
- If the script is being run for the first time, it will parse through all most recent tweets (maximum 100, which usually goes back 3-5 days).
- If the script has run before, it will check if there are new tweets in #opndir (using the “since_id” element from the Twitter standard search API).
  - If there was an update -> parse all the new tweets.
  - If there was no update -> do nothing.
During the parsing of the tweets, the SxTR API is used to retrieve all the observables (using the Inspect API endpoint).
It then removes observables with a clean disposition (retrieved from SxTR API).
It also checks for Target Sightings. If there is a Sighting of a Target, the Webex Teams message and the Case description in Casebook will get a "HIGH PRIOIRTY" tag.
The last step is to create a SxTR Casebook with the retrieved observables. The username and the text of the tweet will be added into the Case. Optionally, a Webex Teams message is sent to a room to update the Threat Responder.

Installation

Clone this repository or download the ZIP file.
Log in to https://visibility.amp.cisco.com/ with your Cisco Security credentials.
Make sure that you have Casebook enabled (+ the Casebook AMP, Threat Grid and Chrome widget, for extended functionality). Please find more information here: https://visibility.amp.cisco.com/#/help/casebooks.
Click on Modules.
Click on API Clients.
Click on Add API Credentials.
Give the API Credentials a name (e.g., Twitter #opendir parser).
Select at least the Casebook and Private Intelligence checkboxes; however, to be sure, you can also click Select All.
Add an optional description if needed.
Click on Add New Client.
The Client ID and Client Secret are now shown to you. Do NOT click on close until you have copy-pasted these credentials to the config.json file in the repository.
It is possible to integrate the script with Webex Teams. In order to do that, an API Access Token and a Room ID need to be entered in the config.json file. Please retrieve your key from: https://developer.webex.com/docs/api/getting-started. Then create a dedicated Webex Teams space for these notifications and retrieve the Room ID from: https://developer.webex.com/docs/api/v1/rooms/list-rooms. Please be aware that the personal token from the getting started page only works for 12 hours. Please follow these steps to request a token per request: https://developer.webex.com/docs/integrations. This is roadmapped for v3.0 of the script.
Make sure you apply for a Twitter developer account. After you have been accepted, you can create a Twitter app, which creates the right credentials to perform API queries.
Make sure that the config.json file looks like this (with the right keys and IDs filled in between the quotes):

{
  "ctr": {
      "client_id": "<client-id-here>",
      "client_password": "<client-password-here>"
  },
  "webex": {
      "access_token": "<access-token-here",
      "room_id": "<room-id-here>"
  },
  "twitter": {
      "token": "<token-here>",
      "token_secret": "<token-secret-here>",
      "consumer_key": "<consumer-key-here>",
      "consumer_secret": "<consumer-secret-here",
      "since_id": 0
  }
}

You are now ready to execute the script. Go to a terminal and change directory to the folder that contains your twitter_search.py and config.json file.
Make sure you have the correct libraries installed by executing the requirements.txt file (using a Python virtual environment!):

python3.6 -m venv twitter_venv
source twitter_venv/bin/activate
pip install -r requirements.txt

Now execute the twitter_search.py script:

python3.6 twitter_search.py

You are now done.

Notes and Road Map