Confirmed breach

CyrusOne data breach

USUnited States · cyrusone.com

A breach of CyrusOne (United States) was added to Have I Been Pwned’s breach database on 7 October 2026. It affected 373,460 accounts. Exposed: Email addresses, Phone numbers, Names, Addresses, Employers and Job titles and more. The breach began on 5 August 2026, 63 days before it was reported.

Status

Confirmed breach

People affected

373,460 accounts

Reported

7 October 2026

Breach began

5 August 2026

Time to tell

63 days

What was exposed

• Email addresses
• Phone numbers
• Names
• Addresses
• Employers
• Job titles
• Support tickets

Sources

• Breach databaseHave I Been Pwned

If CyrusOne had your data

1. Look for CyrusOne’s own notice or letter: it should say what of yours was involved. Keep it.
2. Expect scams that use your details: calls, texts or emails pretending to be CyrusOne, your bank or the police. Never give codes or passwords, never approve a sign-in you did not start, never move money.

• Spot the scams that use leaked data →
• What to do after a data breach →

Email me if CyrusOne has another breach

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From the data breach tracker: official notices, breach databases and the news, every fact with its source. Open data (CC BY 4.0) · How the tracker works · Found a mistake? Tell us and we correct it.