Synthient and Have I Been Pwned: 2B emails and 1.2B passwords have been compromised: How to check if yours is one of them

Massive Credential Leak Exposes 2 Billion Emails and 1.3 Billion Passwords

Security intelligence firm Synthient has uncovered a vast dataset containing 2 billion email addresses and 1.3 billion passwords, compiled from years of prior breaches, malware logs, and dark web marketplaces. Unlike a single hack, this collection aggregates data from multiple incidents both recent and historical highlighting the persistent risk of exposed credentials circulating online indefinitely.

The leaked data has been cross-referenced with Have I Been Pwned, a widely used breach-tracking service, allowing users to check if their email appears in the compilation. The exposure increases the risk of account takeovers, particularly through credential stuffing, where attackers use stolen login details across multiple platforms.

Cybersecurity experts emphasize that reused passwords amplify the threat, as compromised credentials from one breach can grant access to other accounts. The incident underscores the importance of unique passwords, two-factor authentication (2FA), and password managers to mitigate risks. Additionally, running antivirus scans before resetting passwords can help detect lingering malware.

While the dataset spans multiple years, its discovery serves as a reminder of the long-term consequences of data breaches and the need for proactive security measures.

Source: https://www.masslive.com/news/2025/12/2b-emails-and-12b-passwords-have-been-compromised-how-to-check-if-yours-is-one-of-them.html

Synthient cybersecurity rating report: https://www.rankiteo.com/company/synthient

Synthaverse cybersecurity rating report: https://www.rankiteo.com/company/synthaverse

"id": "SYNSYN1768657274",
"linkid": "synthient, synthaverse",
"type": "Breach",
"date": "12/2025",
"severity": "85",
"impact": "4",
"explanation": "Attack with significant impact with customers data leaks"

{'affected_entities': [{'customers_affected': '2 billion email addresses',
                        'type': 'General Public'}],
 'customer_advisories': 'Users can check if their email appears in the '
                        'compilation via Have I Been Pwned. Running antivirus '
                        'scans before resetting passwords is recommended.',
 'data_breach': {'number_of_records_exposed': '3.3 billion (2B emails + 1.3B '
                                              'passwords)',
                 'personally_identifiable_information': 'Email addresses',
                 'sensitivity_of_data': 'High (credentials enabling account '
                                        'takeovers)',
                 'type_of_data_compromised': ['Email addresses', 'Passwords']},
 'description': 'Security intelligence firm Synthient has uncovered a vast '
                'dataset containing 2 billion email addresses and 1.3 billion '
                'passwords, compiled from years of prior breaches, malware '
                'logs, and dark web marketplaces. Unlike a single hack, this '
                'collection aggregates data from multiple incidents both '
                'recent and historical, highlighting the persistent risk of '
                'exposed credentials circulating online indefinitely.',
 'impact': {'data_compromised': '2 billion email addresses and 1.3 billion '
                                'passwords',
            'identity_theft_risk': 'Increased risk of account takeovers and '
                                   'credential stuffing'},
 'initial_access_broker': {'data_sold_on_dark_web': 'Data compiled from dark '
                                                    'web marketplaces'},
 'lessons_learned': 'The incident underscores the importance of unique '
                    'passwords, two-factor authentication (2FA), and password '
                    'managers to mitigate risks. Reused passwords amplify the '
                    'threat of credential stuffing.',
 'post_incident_analysis': {'root_causes': 'Aggregation of data from multiple '
                                           'prior breaches, malware logs, and '
                                           'dark web sources'},
 'recommendations': ['Use unique passwords for each account',
                     'Enable two-factor authentication (2FA)',
                     'Use password managers',
                     'Run antivirus scans before resetting passwords'],
 'references': [{'source': 'Have I Been Pwned'}],
 'response': {'remediation_measures': 'Users advised to use unique passwords, '
                                      'two-factor authentication (2FA), and '
                                      'password managers'},
 'title': 'Massive Credential Leak Exposes 2 Billion Emails and 1.3 Billion '
          'Passwords',
 'type': 'Credential Leak'}