Verified Breach

Aug 5, 2026 Breach Date

373,460 Accounts Affected

7 Data Types Exposed

Oct 7, 2026 Added to HIBP

About This Breach

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.

Compromised Data Types

Email addresses Employers Job titles Names Phone numbers Physical addresses Support tickets

Read our full analysis of this breach →

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1. Purpose: This tool checks whether your email address has appeared in publicly known data breaches via the Have I Been Pwned (HIBP) API.

2. Data Collection: Your email address is submitted to HIBP for breach lookup. If lead capture is enabled, your email may also be stored locally for service communication. Your IP address is recorded alongside it and used for rate limiting and abuse prevention. Past the daily limit of free checks, you will be asked for your email address and a 6-digit code we send to it; free checks are counted per IP address, stored in hashed form, for the day.

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CyrusOne Data Breach

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