Was hoyletanner.com hit by ransomware?

hoyletanner.com was listed by the Braincipher ransomware operation (United Kingdom), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the Braincipher ransomware group?

Braincipher is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the hoyletanner.com breach?

Braincipher published data attributed to hoyletanner.com. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Hoyle Tanner

listed as hoyletanner.com · Claimed by BrainCipher · listed 6 hours ago

Today

Age

since listed · data leaked

Status timeline

ListedSep 17, 2026
Data leakeddate unknown

At a glance

Group: BrainCipher
Status: Data leaked
Country: United Kingdom
Sector: Professional Services
Listed on leak site: Sep 17, 2026

About the victim

AI dossier — public-source company profile

Hoyle Tanner is a civil engineering and infrastructure consulting firm founded in 1973, specializing in planning and design services for aviation, bridges, roadways, water systems, and municipal projects. The firm has completed nearly 13,000 projects and serves public agencies, municipalities, and private developers.

Industry: Civil Engineering & Infrastructure Consulting
Founded: 1973

Attack summary

Severity: high — Confirmed exfiltration of 33,500 files containing sensitive business data: customer database, banking/ACH documents, payroll, tax forms, and infrastructure plans for critical infrastructure projects. Data published with no indication of redaction.

BrainCipher claims to have exfiltrated 33,500 files from Hoyle Tanner, including contracts, proposals, customer databases, HR records, tax forms, banking documents, payroll, insurance information, infrastructure plans, and drone photography. The group published the data and set a ransom deadline of September 25, 2026.

high

Data the group says was taken

AI dossier — extracted from the leak post

Contracts and agreements
Commercial proposals
Invoices
Customer database
HR records
W-9 tax forms
ACH/banking documents
Payroll records
Tax documents
Insurance information
Account information
Infrastructure plans and drawings
Drone aerial photography

Original description

AI-summarised, not from the leak post

N/A

The leak post

captured from the group's site

We have 33,500 (33.5k) files, the contents of which include: Contracts and agreements; Commercial proposals; Invoices; Customer database; HR ; W-9 tax forms; ACH/banking documents; Payroll; Taxes; Insurance; Account information; Infrastructure plans and drawings; Drone aerial photography; If you think you are here by mistake, please contact us at [email protected]
⏳ Deadline: September 25, 2026 at 13:00

Sources

Victim sitehoyletanner.com
Leak posthttp://vkvsgl7lhipjirmz6j5ubp3w3bwvxgcdbpi3fsbqngfynetqtw4w5hyd.onion/n/hoyletanner-com

Source

Indexed 6 hours 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 Braincipher

Braincipher is a recently emerged ransomware group that was first observed in July 2024, operating with apparent financial motivations and targeting organizations primarily across North America and Europe. The group's origin and potential affiliations remain largely undocumented by major threat intelligence organizations, though their targeting patterns suggest a broad opportunistic approach rather than nation-state backing, likely operating as an independent entity rather than through established ransomware-as-a-service infrastructure. Their attack methodology and specific technical capabilities have not been extensively documented by CISA, FBI, or major security research firms, though their victim distribution across 44 confirmed targets spanning business services, manufacturing, technology, and healthcare sectors indicates a generalist approach to target selection rather than sector-specific expertise. No major high-profile campaigns or significant law enforcement actions have been publicly documented against this group by reputable sources, suggesting either a relatively low-impact operational scale or insufficient intelligence collection on their activities. As of current reporting, the group's operational status remains unclear due to limited public documentation from established threat intelligence sources. The group has been linked to 81 public disclosures across our corpus. First observed on a leak site on July 1, 2024; most recent post September 17, 2026. The operation is currently active.

Also tracked as: brain cipher.

Timeline of this disclosure

September 17, 2026hoyletanner.com listed by Braincipher on the group's public leak site

Other recent disclosures by Braincipher

Braincipher has been linked to 81 public victims on Darkfield. A sample of the most recent:

See the full Braincipher dossier →

Sector and geography

This disclosure adds to ransomware activity in the Professional Services sector, which has 17 disclosures indexed across all operators we track. Geographically, hoyletanner.com is reported in United Kingdom, a country with 377 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Braincipher means hoyletanner.com 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 Braincipher'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.