Data breach
CyrusOne data breach
373,460 accounts · breached August 5, 2026
What happened
In August 2026, data centre operator CyrusOne was the target of a ShinyHunters "pay or leak" extortion attempt. The group subsequently published data allegedly obtained from the company, which included 373k unique email addresses across records relating to users, sales leads and CyrusOne employees. The data largely consisted of corporate contact information, including names, physical addresses, phone numbers and job titles. It also included support tickets and other information related to the organisation's operations.
What data leaked
- Email addresses
- Employers
- Job titles
- Names
- Phone numbers
- Physical addresses
- Support tickets
What to do if you had an account
- Turn on two-step sign-in. Enable two-factor authentication where the service offers it, preferably with an authenticator app or a passkey. A leaked password alone is then not enough to get in.
- Expect targeted phishing. Leaked contact details are used to write convincing fake messages that mention the breached company or your real name. Do not click links in unexpected emails or texts about this account; go to the site by typing its address.
- Watch for scam calls and SIM swaps. Be suspicious of calls and texts that claim to be from your bank or a courier. Ask your mobile operator for a port-out or SIM-change PIN if it offers one.
Check your email at haveibeenpwned.com
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