Synthient Aggregated Stealer Logs 2025.0 Data Breach
ObscureIQ Breach Intelligence
High SeverityWebsite / service breach
Synthient Infostealer Threat Intelligence Compilation (2025): 183 Million Email Addresses Aggregated from Criminal Sources
Credential theft and device data exfiltration.
Verified by ObscureIQ Intelligence
60/100Breach Risk Index
20Data Value
40Market Recency
260dSince Breach
Breach Intelligence Summary
Entity: Synthient Aggregated Stealer Logs · Actor: Unknown (infostealer operators) · Sources: 2 references
Attack: Malware / Infostealer
Profile: Malware / Infostealer · Credential theft and device data exfiltration · Aggregated infostealer threat dataset · Global
Timeline: Breach (2025-04-01) · Indexed (Oct 21, 2025) · Year (2025.0)
Exposure: Undisclosed records · 2 fields: Email Address, Password
Status: Compilation
Executive Summary
In October 2025, threat-intelligence firm Synthient shared a corpus of infostealer logs (about 3.5TB, 23 billion rows) containing 183 million unique email addresses along with the passwords used and the websites they were entered into. About 16.4 million email addresses had never been seen in prior breaches. The data was captured by infostealer malware on infected devices.
ObscureIQ assessment: Exposure extends to every credential entered on a compromised device until passwords are reset and the malware removed.
Breach Impact
Live infostealer credentials tied to the exact target site are highly actionable for account takeover; presence typically indicates a device was infected rather than one site being breached.
About Synthient Aggregated Stealer Logs
This record is an aggregated corpus of information-stealer (infostealer) logs compiled by threat-intelligence firm Synthient, not a breach of a single organization.
Why They Hold Your Data
Stealer threat datasets aggregate exfiltrated credentials, cookies, device details, and browser data from many sources into a structured corpus built for analysis or detection of compromised identities. Their workflows involve ingesting raw stealer logs, normalizing fields, de-duplicating records, and mapping exposed accounts or devices.
Recent Developments
In October 2025, Synthient shared the corpus with Have I Been Pwned; it was the first tranche of a much larger threat-data collection.
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 (infostealer operators)
Unknown (infostealer operators)
Malware / Infostealer
Attribution and method are based on available breach intelligence. Reported attack vector: Malware / Infostealer.
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 Aggregated Stealer Logs breach?▾
In October 2025, threat-intelligence firm Synthient shared a corpus of infostealer logs (about 3.5TB, 23 billion rows) containing 183 million unique email addresses along with the passwords used and the websites they were entered into. About 16.4 million email addresses had never been seen in prior…
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
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