183M accounts from Synthient Stealer Log Threat Data were exposed in this breach. Besides email addresses, it included passwords, which makes it a high-risk breach.
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Email addressesPasswords
During 2025, Synthient aggregated billions of records of "threat data" from various internet sources. The data contained 183M unique email addresses alongside the websites they were entered into and the passwords used. After normalising and deduplicating the data, 183 million unique email addresses remained, each linked to the website where the credentials were captured, and the password used. This dataset is now searchable in HIBP by email address, password, domain, and the site on which the credentials were entered.
Source: Have I Been Pwned (CC BY 4.0)