Synthient Credential Stuffing Lists 2025.0 Data Breach
ObscureIQ Breach Intelligence
Moderate SeverityWebsite / service breach
Synthient Credential Stuffing Intelligence Report (2025): 2 Billion Exposed Email Addresses Aggregated
Aggregated stolen credentials and password pairs.
Verified by ObscureIQ Intelligence
56/100Breach Risk Index
17Data Value
40Market Recency
244dSince Breach
Breach Intelligence Summary
Entity: Synthient Credential Stuffing Lists · Actor: Unknown (aggregator) · Sources: 2 references
Attack: Scraping / Collection
Profile: Breach Compilation · Aggregated stolen credentials and password pairs · Credential stuffing threat dataset · Global
Timeline: Breach (2025-04-01) · Indexed (Nov 06, 2025) · Year (2025.0)
Exposure: Undisclosed records · 2 fields: Email Address, Password
Status: Compilation
Executive Summary
In 2025, Synthient aggregated credential-stuffing lists from across the internet, and Have I Been Pwned indexed 1,957,476,021 unique email addresses (about 2 billion) and 1.3 billion unique passwords on 5 November 2025. These lists combine credentials from prior breaches and are used to attack unrelated accounts where victims reused passwords. Of HIBP’s subscribers, nearly half were found in the dataset.
ObscureIQ assessment: Mitigation is unique passwords and MFA rather than action against any single company; scale makes reuse especially dangerous.
Breach Impact
As a giant credential-stuffing resource, its danger is the breadth of reusable email/password pairs; presence indicates a credential is circulating for reuse attacks, not that a specific company was breached.
About Synthient Credential Stuffing Lists
This record is an aggregation of credential-stuffing lists compiled from many sources by threat-intelligence firm Synthient, not a breach of any single organization.
Why They Hold Your Data
Credential stuffing threat datasets aggregate email addresses, usernames, passwords, and tested login pairs from many prior compromises into a cleaned corpus built for large-scale validation and reuse. Their workflows center on collecting leaked credentials, standardizing formats, de-duplicating entries, and mapping them to likely target services.
Recent Developments
Have I Been Pwned completed processing the corpus on 5 November 2025 as a separate dataset from the Synthient stealer logs.
Data Points Exposed
2 verified field types
Email Address
Password Critical
Field names are shown in full for clarity and search visibility. Canonical machine keys are emitted only in this page’s structured data.
Exploitation & Downstream Threats
Threat Activity:High
Primary downstream threats:
Threat vectors:
- Phishing, credential stuffing & account takeover
- Credential stuffing & account takeover
Threat Actor: Unknown (aggregator)
Unknown (aggregator)
Scraping / Collection
Attribution and method are based on available breach intelligence. Reported attack vector: Scraping / Collection.
Recommended Actions
If you believe your information may be included:
Change Reused Passwords
Update this account and anywhere you reused the password; use a manager.
Enable MFA Everywhere
Turn on multi-factor authentication on email first, then financial accounts.
Report & Recover
If you spot misuse, start an official recovery plan and report fraud.
Frequently Asked Questions
What happened in the Synthient Credential Stuffing Lists breach?▾
In 2025, Synthient aggregated credential-stuffing lists from across the internet, and Have I Been Pwned indexed 1,957,476,021 unique email addresses (about 2 billion) and 1.3 billion unique passwords on 5 November 2025. These lists combine credentials from prior breaches and are used to attack…
What data was exposed?▾
Verified fields include Email Address, Password.
What should I do if I was affected?▾
Change reused passwords, enable MFA, and (if identity or financial data is involved) freeze your credit and monitor your accounts.
Sources & References
Every claim on this page is traceable. This breach draws on:
Breach Index
ObscureIQ Intelligence
ObscureIQ proprietary analysis
Protect Yourself
Check If You're Affected
Enter your email to check whether your data appears in this breach. We’ll send a 6-digit code to confirm it’s your address.
Get Free Breach Alerts
Be the first to know when new breaches are disclosed. Free forever — confirm your email with a 6-digit code.
High-Risk? Get an Exposure Audit
Executives, public figures, and high-visibility operators can receive tailored exposure intelligence and hardening guidance.
Request Consultation