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Arup Group

Claimed by Fulcrumsec · listed 2 months ago

2m
Age
since listed · data leaked

Status timeline

  1. ListedMay 10, 2026
  2. Data leakeddate unknown

At a glance

Group
Fulcrumsec
Status
Data leaked
Country
United Kingdom
Sector
Business Services
Listed on leak site
May 10, 2026

About the victim

AI dossier — public-source company profile

Arup Group is a British multidisciplinary engineering and architecture consultancy founded in 1946 by Sir Ove Arup. The firm is employee-owned through a trust structure, employs approximately 17,000 people across 90 offices in 34 countries, and generates roughly £2.16 billion in annual revenue. Arup is responsible for landmark projects including the Sydney Opera House, the Pompidou Centre, and Beijing's CCTV Headquarters, and operates proprietary software subsidiaries including Oasys and NeuronCloud.

Industry
Engineering & Architecture Consultancy
Address
13 Fitzroy Street, London, W1T 4BQ, United Kingdom
Employees
17000
Founded
1946

Attack summary

Severity: critical — Confirmed exfiltration of ~5 TB of data including large-scale PII (129,000+ named landowners with addresses and financial details, 313,650 surveillance records), sensitive infrastructure data for critical national projects (HS2, major transport), commercial source code of sold software products, valid cryptographic certificates and private keys, client operational data for named entities including a hospital, and physical security vulnerability maps of Arup's own premises — spanning multiple cat

The group claims to have exfiltrated approximately 5 terabytes of data between September 2025 and April 2026 via a hardcoded GitHub personal access token, pivoting through Azure Blob Storage, AWS S3, and database infrastructure; no encryption of systems is claimed. Data published includes over 700 GB of private GitHub repositories, nearly 2 TB of cloud storage and database backups, 313,650 surveillance records, 129,000+ landowner PII files, proprietary source code, credentials, and certificates.

critical

Data the group says was taken

AI dossier — extracted from the leak post
  • Private GitHub repositories (9,880+ repos, ~700 GB compressed)
  • Azure Blob Storage contents (29 accounts, ~2 TB)
  • AWS S3 bucket contents (44 Neuron buckets)
  • AWS Redshift and RDS database backups
  • Neo4j graph database contents
  • 39 Neuron BMS client databases (Hong Kong)
  • 49 GB Odoo ERP data
  • 129,455 A66 landowner PII files (names, addresses, financial negotiation details)
  • 120,000+ compulsory purchase process emails (.msg)
  • 313,650 ICC surveillance records
  • 37,835 Queensferry Crossing internal documents
  • ArupCompute proprietary engineering platform source code
  • Oasys GSA, AdSec, and Compos commercial software source code
  • NeuronCloud smart building IoT platform source code and client configs
  • Tunnel optimisation algorithm source code (HS2, Melbourne Metro, Ontario Line)
  • HS2 Euston Station engineering data and 14,000+ sensor records
  • Amazon facility seismic vulnerability assessments (named Seattle sites)
  • BP Clean Energy Logistics Hub site selection data with geocoordinates
  • Arup office physical security vulnerability assessments
  • Apple Enterprise and Developer ID code-signing certificates with plaintext passwords
  • Oasys commercial code-signing certificate
  • RSA private keys for IoT gateways (Kings Cross, 8 Fitzroy Street)
  • Azure AD client secrets
  • AWS access keys
  • SharePoint OAuth credentials
  • GCP production payment gateway credentials
  • SSL certificates
  • Hardcoded database connection strings
  • Oasys GSA P-Delta calculation defect documentation (Jira export)

Original description

AI-summarised, not from the leak post

Arup Group is a British multinational professional services firm headquartered in London, United Kingdom. Founded in 1946, it operates in the engineering, design, planning, and consulting industries. The firm provides structural, civil, mechanical, and electrical engineering services, alongside architecture and project management. Arup works across sectors including infrastructure, buildings, transport, and energy, delivering projects in over 140 countries worldwide.

The leak post

captured from the group's site
[DOWNLOAD GITHUB REPOS (~377 GB compressed — onion link)](http://4e3p3in2bl67hxchuwza7qvnpe7pyeloyztr5fnh257fxkovfhappjyd.onion/arup-repos-data/) [AZURE STORAGE, NEURON S3 & DATABASES — FULL ARCHIVE LIST](http://4e3p3in2bl67hxchuwza7qvnpe7pyeloyztr5fnh257fxkovfhappjyd.onion/arup/archives/)
Over 700 GB of private GitHub repositories • nearly 2 TB of Azure Blob Storage, AWS S3 buckets, and database backups • 9,880+ private repos • 39 Neuron BMS client databases • 49 GB of Odoo ERP • 129,000+ A66 landowner files • 313,650 ICC surveillance records • 37,835 Queensferry Crossing internal documents • Apple code-signing certificates with plaintext passwords • the complete ArupCompute and Oasys source code
Arup Group is a British engineering consultancy founded in 1946 by Sir Ove Arup. They are employee-owned through a trust structure, employ about 17,000 people across 90 offices in 34 countries, and generate roughly £2.16 billion in annual revenue. They engineered the Sydney Opera House, the Pompidou Centre, and Beijing’s CCTV Headquarters. They are good at what they do.
This is a difficult breach to write up for several reasons.
1) We spent close to half a year analysing the data, the mos…

Sources

Source

Indexed 2 months ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About fulcrumsec

FulcrumSec is a recently emerged ransomware group that was first observed in May 2026, operating with apparent financial motivations based on their targeting patterns across multiple countries and high-value sectors. Given the recency of their emergence and limited public documentation, the group's specific country of origin and potential affiliations remain unclear, though their targeting of victims across the United States, India, Netherlands, Colombia, and Japan suggests either a geographically distributed operation or deliberate international scope rather than nation-state backing. The group has demonstrated a preference for targeting technology companies, business services firms, and healthcare organizations, with 21 documented victims indicating a selective approach focused on sectors likely to yield significant ransom payments due to operational dependencies and sensitive data holdings. Their attack methodology details remain largely undocumented in public threat intelligence reports from major security firms, though their sector targeting suggests sophisticated initial access capabilities given the typically robust security postures of technology and healthcare organizations. No major high-profile campaigns or significant law enforcement actions against FulcrumSec have been publicly reported by CISA, FBI, or leading cybersecurity researchers as of available intelligence. The group appears to remain active as of the most recent observations, though the limited public intelligence on their operations suggests they may be maintaining a relatively low profile compared to more established ransomware enterprises. The group has been linked to 25 public disclosures across our corpus. First observed on a leak site on May 1, 2026; most recent post June 16, 2026. The operation is currently active.

Timeline of this disclosure

  • May 10, 2026Arup Group listed by fulcrumsecon the group's public leak site

Other recent disclosures by fulcrumsec

fulcrumsec has been linked to 25 public victims on Darkfield. A sample of the most recent:

See the full fulcrumsec dossier →

Sector and geography

This disclosure adds to ransomware activity in the Business Services sector, which has 3,796 disclosures indexed across all operators we track. Geographically, Arup Group is reported in United Kingdom, a country with 373 ransomware disclosures in our corpus.

If your organisation is affected

A listing by fulcrumsec means Arup Group appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

  • Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
  • Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
  • Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
  • Report the incident to your national CERT, NCSC (United Kingdom), as required for your jurisdiction.
  • Monitor for the data appearing on fulcrumsec's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.