What Happened:

• On 10 May 2026, the UK-based firm Arup Group was listed as a victim on the Tor data leak site of FulcrumSec. 
• On their Tor data leak site, FulcrumSec stated that they have exposed 700GB of GitHub repos and 2TB of Azure and AWS S3 cloud, plus database backups.
• Other types of data the adversary claims to have stolen includes Neuron BMS client databases, Odoo ERP data, A66 landowner files, Apple code-signing certificates with plaintext passwords, a Google Cloud Platform (GCP) project with production payment gateway credentials, and the source code of ArupCompute and Oasys. 
• The FulcrumSec operators also claimed to have spent over half a year analysing the data and went through “email correspondence” with the company before publishing the stolen data.
• On the victim post, FulcrumSec wrote a detailed incident breakdown. In it, they stated they gained initial access in September 2025 via a GitHub personal access token found hardcoded in a JavaScript file on a forgotten subdomain, which provided access to over 10,000 private GitHub repositories belonging to Arup Group.
• From there, they scanned the repositories and found additional hardcoded tokens, API keys, and passwords for AWS, Azure, and databases.
• The adversary stated that Arup detected the Github and Azure Storage intrusions approximately six weeks after they happened and rotated the credentials, but it was too late as the data had been exfiltrated. 
• FulcrumSec also stated they pivoted into the AWS infrastructure using keys they had found belonging to Arup’s subsidiary Neuron.
• FulcrumSec allegedly waited until April 2026 to contact their victim, Arup Group, due to the time it took to analyse the vast amounts of stolen data.
• Impacted client organisations of Arup Group were also mentioned in the post, such as Disney and several other Hong Kong companies. The adversary reportedly uncovered Amazon data center seismic fragility data, British Petroleum (BP) site selection coordinates, and Queensferry Crossing internal documents as well.
• Critically for the UK, the breached data exposed up to 62 HS2 related GitHub repositories. This involved Euston Station pile design files, ground movement assessments, over 14,000 sensor monitoring records, 48 archaeological site GPS coordinates (including Jones Hill Wood, a sensitive site for environmentalists), as well as confidential documents.

Analyst Comment:

Arup Group is a large multinational architectural design and engineering firm based in London who has been involved in constructing the Wembley Football Stadium in London, the HS1 Channel Tunnel Rail Link network, and the Eden Project in Cornwall, among other significant international construction projects.

Active since September 2025, FulcrumSec is a financially motivated data-theft-extortion group that specialises in rapid exfiltration of cloud-hosted databases by exploiting unrotated API keys and misconfigured cloud permissions.

This attack was noteworthy due to its highly targeted nature. FulcrumSec claimed they had access to Arup Group’s data for seven months and they clearly invested significant time to analyse the documents and spent weeks negotiating over email. Plus, to find initial access they also would have had to spend time checking Arup’s domains and Internet-facing assets to eventually find a single leaked credential to exploit. These types of targeted intrusions often only happen to large companies. This is because for it to be worth the cybercriminal’s time, effort, and risk to their freedom they will want a large ransom payment that only rich companies can typically afford.

FulcrumSec is an adversary worth monitoring due to the effort they put into their intrusions compared to other smash-and-grab ransomware campaigns. In October 2025, in a case documented by VX-Underground, FulcrumSec emailed detailed information about the breach they conducted with the aim of those details getting published and exert additional pressure on the victim.

Interestingly, FulcrumSec said the ransom they demanded was less than 1% of Arup’s annual revenue and was less than how much Arup lost to the deepfake fraudsters. This is a reference to Arup reportedly lost over £20 million pounds in 2024 after one of their Hong Kong employees was duped into sending cash to cybercriminals using an AI-generated video call. The fact Arup became publicly known for falling victim to a large scam potentially contributed to the adversary’s decision to select and focus them for this attack.

Defensive Takeaways:

• Asset Inventory and Shadow IT Audits: Identifying the outdated unused domains with hardcoded credentials is standard best practices. All organisations must have processes in place to catalog and retire systems to avoid incidents like this. 
• Hardcoded Credentials in Code: They way FulcrumSec gained access demonstrates the importance of using secret environment variables and features like GitHub Secret Scanning.
• Implement Incident Response Procedures: Importantly, Arup detect the activity too late and it took them a staggering six weeks to rotate credentials (according to the adversary), which shows why having automated systems to check for unauthorised usage and reset tokens and all accounts is crucial to respond to such attacks.
• GitHub Activity Monitoring: The adversary claimed they were able to clone thousands of GitHub repositories containing sensitive data without being detected. These types of activities are available to monitor and detect in GitHub Audit Logs. It’s also important to have a plan in place when suspicious activities are detected.
• Third-Party Risk Management Programs: This incident also had some notable downstream impact. It shows why client organisations of another company’s services need to know what data and how much data is stored by third-parties for when such breaches occur. Knowing what’s potentially exposed will streamline the response to the incident.
• Deception Tech: Arup could have implemented a boobytraps for the adversary such as the use of CanaryTokens inside sensitive documents. As the adversary spent time analysing the Arup’s documents before contacting them, if they open a boobytrapped document, then the incident could been detected much earlier and the damages could have been reduced.

Relevant Sources:

1. https://x.com/darkwebinformer/status/2053281385582891437 
2. https://www.ransomware.live/id/QXJ1cCBHcm91cEBmdWxjcnVtc2Vj 
3. https://en.wikipedia.org/wiki/Arup_Group
4. https://www.theguardian.com/technology/article/2024/may/17/uk-engineering-arup-deepfake-scam-hong-kong-ai-video

Relevant CTI Resources:

1. https://www.ransomware.live/group/fulcrumsec
2. https://x.com/vxunderground/status/1975629199323853027 
3. https://www.reddit.com/r/Scams/s/wfZ3Wp94mY
4. https://www.bleepingcomputer.com/news/security/lexisnexis-confirms-data-breach-as-hackers-leak-stolen-files/

Introduction

The Ransomware Tool Matrix continues to be a useful passion project that I am happy to continue maintaining. One piece of common feedback I've received for the Ransomware Tool Matrix was that individuals would like to contribute their observations to it, but do not have public links they can cite (such as a formal blog post on a company website). Therefore, I came up with a plan to make a reporting template to help with this.

What are Community Reports?

Individuals can now share what tools they have seen various ransomware groups, affiliates, or initial access brokers (IABs) use via the new Community Report Template. The level of detail provided is the contributor's choice. The more verifiable information shared, the increased level of reliability and credibility.

You can view the current list of Community Reports on GitHub here.

Why the need for Community Reports?

Most of the sources of CTI about ransomware TTPs comes from open source reports by organisations such as the US Cybersecurity and Infrastructure Security Agency (CISA), The DFIR Report, and other cybersecurity vendors. From the beginning it was important to recognise the importance of the having public citations by reputable organisations to maintain the reliability and credibility of the resource overall. Consumers of the Ransomware Tool Matrix should feel confident that the information provided is of high standard and legitimate.

The problem was, however, that members of the cybersecurity community who may work with victims of ransomware attacks also have information about what tools which ransomware group uses. 

The sources of this information could come from various sources, such as from Digital Forensics and Incident Response (DFIR) service providers, Managed Security Service Providers (MSSPs), Endpoint Detection and Response (EDR) vendors, or security researchers who manage to obtain threat intelligence about ransomware groups via various other means, such as infiltrating cybercrime forums or open directory hunting.

These sources of information did not currently have a way to contribute to the Ransomware Tool Matrix due to the missing factor of a publicly citable blog.

How do Community Reports work?

Members of the Community with information and tools used by ransomware groups can now share their observations via a structured report template shown below.

Whether to include all the details here is up to the contributor, but this type of reporting system is an option for community members to share their findings with the rest of the community who are interested in this information.

Anyone who wants to submit a Community Report can copy the code, edit in their findings, and submit a pull request to the GitHub repository. Alternatively, they can fork the project and then I can merge their commits to the main branch. More details about how to creating a pull request from a fork can be found in the GitHub's Docs here.

Conclusion

One of the problems of cybersecurity vendor blogs is that a lot of them are marketing material and therefore, details about every ransomware incident a company worked on is not great marketing. However, as CTI analysts, incident responders, threat hunters, and detection engineers, these details are crucial for our day-to-day lives. Hence why the Community Report system was one of the most common pieces of feedback I received and why I created it.

I look forward to the contributions from the community to this new reporting system and hope it helps many more who are keen to see and read about what the latest tools are that the ransomware cybercriminals are using.