Tokyo Himitsukichi
Tokyo, Japan1 source
Claimed:Claimed on a ransomware leak site on 31 Oct 2026. Not confirmed by the organisation, so treat it as a claim, not a fact.
Tokyo Himitsukichi hacker publishes additional patient data
A hacker published additional customer and therapist data on 31 October, claiming to identify about 2,700 users by real name.
- Type
- Data breach
- Sector
- Healthcare
- Records
- 2.7K records reported
- First reported
- 31 Oct 2026
- Latest source
- 31 Oct 2026
What to do
- This is only a claim by the attackers so far. Do not panic, but do the basics:
- If you have an account, change that password, and anywhere you reused it.
- Turn on two-factor authentication, ideally an authenticator app or passkey, not SMS.
- Treat this as unverified. Ask the organisation directly before acting on it.
- If this is a vendor of yours, ask what of your data they held and whether it was in scope.
- Reset any API keys, SSO trusts or shared credentials you have with them.
Not sure? Ask an assistant with the sources attached, or have a coding agent check your systems.
Check your systems for Tokyo Himitsukichi
Sources
1Confidence 60% that this is real and correctly placed. Locations are city centroids at best. Spotted an error? Report a correction.