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.
Thunder rolls, lightning strikes & the hammer flies across the sky.
God of the weather,
chariot of the storm,
master of rain & torrents.
Son of the strength
of Mother Earth,
I ask you to grant me that strength for myself.
What is THOR Thunderstorm?
A RESTful web service that receives samples and returns a scan result. It is feature-rich and very fast.
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
By using it in a container that scales with the demand, you can process millions of files in a few minutes.
Most operating system provide tools to walk the file system and submit files via HTTP. The following examples are intentionally short and compact to inspire you with their simplicity. Think of all devices that you could analyze this way. No agent, no portable scanner, just simple file submission via HTTP.
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 following slide lists the different components that can be used with THOR Thunderstorm. We provide a server installer script, collectors, a Python API client and update scripts.
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.”
Low CPU and RAM Usage
A collection task requires 0.75-2% of the CPU and 20MB memory.
Any OS, Any Arch
Our collectors run on any operating system and processor architecture
It allows ultra fast collection runs. (Our tests: Win 10, collect last 3 days, any type, full disk = 3 minutes run)
Thunderstorm API Client
We provide a Python module and Python based API client that supports multi-threaded submission to the THOR Thunderstorm service.
Modes of Operation
The service can be started in two scan modes:
- Pure YARA
Completely On Premise
THOR Thunderstorm can be installed on any internal system and runs as a service within your network
Store suspicious or all transmitted samples with a reference to the source system to facilitate the deeper analysis
THOR Thunderstorm supports the analysis of different file types that get collected for forensic analysis purposes (e.g. EVTX files, Registry Hives)
Custom Signatures and IOCs
Add you own YARA signatures, Sigma rules, hash and filename IOCs and apply them to incoming samples
THOR Thunderstorm offers many ways to output information (Text, JSON, Syslog), which makes it easy to integrate the findings into your favorite SIEM system
Web GUI and API Documentation
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.
On The Roadmap
The following tasks are on our roadmap for THOR Thunderstorm
- Collector service that uses file system notifications to submit new files in real-time
- Cortex Analyzer
- ICAP Support (allows interfacing with Web Proxies)
- File format support: PCAP, MFT
- Recursive extraction of nested archives
- Docker setup guide