Synthient Credential Stuffing Threat Data data breach
1,957,476,021 accounts exposed.
Check whether your email is included on Have I Been Pwned.
What was exposed
Email addressesPasswords
What to do
- Change your Synthient Credential Stuffing Threat Data password, and the password on any other site where you used the same one.
- Expect more phishing emails that mention this service. Do not click links in them; go to the site directly.
- Turn on two-step verification wherever it is offered, and use a password manager.
About this breach
During 2025, the threat-intelligence firm Synthient aggregated 2 billion unique email addresses disclosed in credential-stuffing lists found across multiple malicious internet sources. Comprised of email addresses and passwords from previous data breaches, these lists are used by attackers to compromise other, unrelated accounts of victims who have reused their passwords. The data also included 1.3 billion unique passwords, which are now searchable in Pwned Passwords. Working to turn breached data into awareness, Synthient partnered with HIBP to help victims of cybercrime understand their exposure.