Science & Tech · Cybersecurity · 1 hr ago
GMO says hackers posted data linked to customers after cloud service breach
Hackers posted information they said belonged to GMO customers after breaching the Japanese company’s Onamae cloud desktop service.
The service provides virtual desktops used by financial traders, and GMO says unauthorized access led to customer information being taken.
GMO has not confirmed whether the published information is genuine, and says it is still checking what was exposed.
The company has warned that as many as 27,000 servers may be affected and has urged customers to reset their passwords.
Some customers reported trading-account activity they did not recognize, raising concern that the breach could affect their finances as well as their personal data.
The attacker demanded money, but GMO says it will not pay because payment would not ensure the data is deleted or kept from being misused.
GMO is investigating and offering customers compensation and alternative service, while asking them not to access or spread the published information.
A suspected attacker posted information said to belong to GMO Internet and its customers, while the company said it was checking whether the material was genuine.
GMO urged people not to access or spread the information and said it may take legal action over malicious distribution.
The attack targeted GMO’s Onamae cloud desktop service, used by financial traders, and the company said up to 27,000 servers may be affected.
GMO said the attacker demanded money and that it would not comply.
The company advised customers to change passwords and take steps to protect their devices and trading accounts.
- Who
- A suspected attacker targeted GMO Internet and posted information said to belong to the company and its customers.
- What
- Information presented as customer data was published online. GMO said it was verifying the material and warned people not to access or spread it.
- When
- The information was reported as posted on October 27, 2026.
- Where
- The attack involved GMO’s Onamae cloud desktop service in Japan; the information was posted online.
- Why
- The attacker demanded money and threatened to publish customer information and take other actions, according to the articles.
GMO Internet
The attacker
Publication of information
GMO Internet
GMO urged people not to access or spread the posted material and said it was checking whether it was genuine.
The attacker
The attacker posted information presented as belonging to GMO and its customers.
Payment demand
GMO Internet
GMO said it would not meet the attacker’s demand.
The attacker
The attacker demanded money and threatened further actions if it was not paid.
GMO Internet shut down its Onamae Desktop Cloud service after discovering unauthorized access and received a ransom demand.
GMO reported the incident to Japanese police and issued a public update.
GMO said it would offer compensation and an alternative service while seeking help from government agencies.
GMO began collecting customers’ devices to check for malware and assess the damage.
The attacker posted information said to be linked to GMO and its customers, and the company said it was checking whether it was genuine.
- Potentially affected servers
- Up to 27,000, according to GMO
- Ransom demand
- $50 million, according to TechCrunch and The Register
- Demand reported by 日本経済新聞
- $1 million by noon on October 27
- Posted data
- Information presented as belonging to one customer, including a name, birth date, address and telephone number
- Customer payment
- ¥5,000 offered to service users, according to The Register
5 sources
Japan internet giant GMO says hackers posted stolen customer data
BREAKING NEWS: GMO Internet Group to offer $1 mil. in cash rewards for hacker info
GMO不正アクセス、攻撃者が「個人情報」公開 拡散なら法的措置
Japanese virtual desktop cloud hacked so hard it asks to be banned
What people are saying
国民の財産などに被害が及ぶ恐れがあるものと認識している
卑劣な行為は断じて許されるものではない
unauthorized operations
complying would not guarantee that the obtained information is deleted or that its misuse is prevented.