We are proud to announce a groundbreaking new scan mode named “Thunderstorm” that we’ve integrated into preview builds of the upcoming THOR version 10.6.

This mode of operation turns THOR into a RESTful web service that is able to process thousands of samples per minute sent from any device within the network.

Think of it as your ultra-fast on-premise scan service, wich is bundled with more than 13,000 hand-crafted YARA rules focusing on persistent threats and forensic artefacts.

Collect files and submit them for analysis from any operating system and any hardware platform. The possibilities are limitless.

With this blog post, we’d like to highlight some of these new possibilities.

Use Case 1 – Remote File Collection

During forensic investigations, automated file collection (ESI) from one or multiple remote systems can be combined with THOR Thunderstorm to improve the forensic anylsis.

Alerts and warnings produced by THOR Thunderstorm highlight interesting elements in file data, registry hives, eventlog files and more.

Use Case 2 – ICS Networks

ICS networks are mission critical, requiring immediate and high-availability. The installation of an endpoint agent or running a portable scanner is often out of question.

With THOR Thunderstorm, you just have to collect and submit the files.

Use Case 3 – Out of Reach Devices

Since file collection is a lot easier than endpoint scanning, all you need is way to export the remote system’s files or directly send them to THOR Thunderstorm.

Imagine that you can collect and submit files from network devices, telephone systems or embedded devices.

Use Case 4 – Out of Reach Operating Systems

File collection scripts for many old or usually unsupported operating systems allow you to upload samples for analysis.

Select files based on size, age or type and schedule frequent upload tasks to analyze only new or modified files. 

Use Case 5 – S3 Bucket Scanning

We’ve been working with our partner Adolus to showcase a tuned version of AirBnb’s BinaryAlert in which the standard YARA analyzer has been replaced by THOR Thunderstorm.

By using it in a container that scales with the demand, you can process millions of files in a few minutes.

Windows 10 Batch

This example shows a simple batch file that walks recursively over a given folder an submits all files. You could extend it to the whole disk and reduce the submission to certain file extensions (e.g. exe, bat, ps1, js).

Linux Web Server

This examples shows how easy it is to get all files in a web server root checked by THOR Thunderstorm just by using bash, find and curl.

The Thunderstorm Collector repository contains a Go based collector, precompiled for many different operating systems and architectures as well as collectors scripts (Batch, Bash, PowerShell).

We have pre-build collectors for Windows, Linux, macOS, AIX, Solaris on x86, x64, Arm, PowerPC, MIPS, RISC-V, Plan9, S390x (IBM Z) architectures.

These collectors allow you select files based on age, size and type for submission to a Thunderstorm server.

It is easy to set up a task like: 

“Select all files that have been created or modified within the last 24 hours and submit them to Thunderstorm for analysis. Run this task daily.”

We provide a Python module and Python based API client that supports multi-threaded submission to the THOR Thunderstorm service.

Service Mode

The service can be started in two scan modes:

• Pure YARA
• Full-Featured

The Web GUI contains important information about the service like the signature set version, uptime, number of processed and queued samples and much more. 

It contains some graphs that help you to assess the actual server load and processing speed. 

It also contains links to the API documentation, the Python API library and the Thunderstorm Collectors for your convenience.