Breach registry
SynthientCredentialStuffingThreatData Data Breach
Synthient Credential Stuffing Threat Data
What was exposed, when it happened, and which databases confirm it.
- accounts
- 1,957,476,021
- Breached
- April 11, 2025
- Last Update
- November 8, 2025
Were you caught in this breach?
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What happened
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.
Compromised Info
- Email addresses
- Passwords
Attestation
Four independent databases catalog this breach and they do not always agree. Each lane below is one source’s own count.
Sources & Link Methods
- HIBP
FAQ
What was leaked in the SynthientCredentialStuffingThreatData breach?
The SynthientCredentialStuffingThreatData breach exposed: Email addresses and Passwords.
When did the SynthientCredentialStuffingThreatData breach happen?
The SynthientCredentialStuffingThreatData breach was disclosed on April 11, 2025 and affected 1,957,476,021 records.
Am I affected by the SynthientCredentialStuffingThreatData breach?
Search your email, phone or username at checkleaked.cc to find out whether your data appears in the SynthientCredentialStuffingThreatData leak.