Breaches · 5h ago
GMO Internet said Oct. 27 that it was verifying customer and business data allegedly posted after unauthorized access to Onamae Desktop Cloud, which may have affected as many as 27,000 servers. The company shut down the service on Oct. 21 after discovering the access.
GMO has not confirmed that the posted material is genuine or established the full scope. It says customers have reported unauthorized operations on trading accounts and advised password resets. Onamae provides virtual desktops used by financial traders, but available reporting does not establish whether the account activity came through the breach.
For financial firms using Onamae for trading workstations, the concern includes transaction integrity, not only exposed data. Resetting passwords may limit future account access, but cannot establish whether past trading activity or the hosted environment was altered; that remains unresolved while GMO verifies the incident.
2 sources covering this story
Japan's GMO urges customers to shut down PCs amid ransomware threat
The GMO Group has urged customers to disconnect their systems from the internet and shut down computers after a threat actor who breached the company's Onamae Desktop Cloud threatened to launch a ransomware attack today.
Japan internet giant GMO says hackers posted stolen customer data | TechCrunch
Japan's GMO Internet is verifying alleged customer data posted by suspected hackers following a cloud service breach.
Part of the PlainSec briefing for 2026-10-27