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株式会社オーエム製作所 (O-M LTD.)

listed as OMLTD.CO.JP · Claimed by RansomHub · listed 1 year ago

15m
Age
since listed · data leaked

Status timeline

  1. ListedMar 24, 2025
  2. Data leakeddate unknown

At a glance

Group
RansomHub
Status
Data leaked
Country
Japan
Listed on leak site
Mar 24, 2025

About the victim

AI dossier — public-source company profile

O-M LTD. is a Japanese manufacturer of precision industrial machinery, including lathes, turning centers, and specialized equipment for heavy industries such as railways, power generation, and aerospace. The company operates multiple facilities and is recognized for precision machining capabilities serving demanding industrial sectors.

Industry
Industrial Machinery Manufacturing & Precision Engineering
Address
〒532-0003 大阪府大阪市淀川区宮原3-5-24 新大阪第一生命ビル8F

Attack summary

Severity: medium — Confirmed ransomware incident with acknowledged personal information leakage, but no specific data volume disclosed, no evidence of operational disruption to critical infrastructure, and no proof files publicly advertised by the group.

RansomHub claims to have compromised O-M LTD., with the company publicly disclosing a ransomware incident and potential personal information leakage in February 2025 and May 2025 notices on their website.

medium

Data the group says was taken

AI dossier — extracted from the leak post
  • personal information
  • employee data
  • business records

Original description

AI-summarised, not from the leak post

N/A

Sources

Source

Indexed 1 year 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 RansomHub

RansomHub is a financially-motivated ransomware group that emerged in February 2024 and has rapidly established itself as a significant threat, compromising over 1,000 victims within its first year of operation. The group operates as a Ransomware-as-a-Service (RaaS) model, though their specific country of origin and potential affiliations with other cybercriminal organizations remain under investigation by security researchers. RansomHub employs double extortion tactics, stealing sensitive data before encrypting victims' systems and threatening to leak the information if ransom demands are not met, with their attacks primarily targeting organizations in the United States, Brazil, Canada, United Kingdom, and Italy. The group has demonstrated a particular focus on business services, technology, manufacturing, and healthcare sectors, suggesting they prioritize targets with both high revenue potential and critical operational dependencies that increase the likelihood of ransom payment. Despite their recent emergence, RansomHub has quickly gained notoriety for their aggressive targeting approach and high victim count, with security agencies including CISA and FBI monitoring their activities as part of ongoing ransomware threat assessments. As of current reporting, RansomHub remains active and continues to recruit affiliates for their RaaS operation while expanding their victim base across multiple industries and geographic regions. The group has been linked to 1,032 public disclosures across our corpus. First observed on a leak site on February 10, 2024; most recent post March 31, 2025. The operation is currently inactive.

Also tracked as: RANSOM HUB.

Timeline of this disclosure

  • March 24, 2025OMLTD.CO.JP listed by RansomHubon the group's public leak site

Other recent disclosures by RansomHub

RansomHub has been linked to 1,032 public victims on Darkfield. A sample of the most recent:

See the full RansomHub dossier →

Sector and geography

Geographically, OMLTD.CO.JP is reported in Japan, a country with 220 ransomware disclosures in our corpus.

If your organisation is affected

A listing by RansomHub means OMLTD.CO.JP 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, JPCERT/CC (Japan), as required for your jurisdiction.
  • Monitor for the data appearing on RansomHub'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.