Brinztech Alert: 185 Million Contact Records from ZoomInfo on Sale

Dark Web News Analysis

A threat of enormous scale targeting the business community has been identified on a cybercrime forum. A threat actor is advertising the sale of a massive database they claim was scraped from the business intelligence platform ZoomInfo in 2024. The dataset is purported to contain 185 million verified business and personal contacts primarily from the United States. The compromised information is exceptionally detailed, including full names, business and personal email addresses, job titles, seniority levels, departments, mobile phone numbers, LinkedIn profile URLs, and extensive company-level data (name, revenue, industry, etc.). The seller claims the data was exfiltrated through the abuse of one of the company’s APIs.

While many data breaches expose consumer PII, the compromise of a ZoomInfo database is uniquely dangerous to the corporate world. This data is specifically curated for B2B sales and marketing, which means it contains the exact organizational and hierarchical information that criminals need to launch devastatingly effective social engineering attacks. Threat actors can use this data to orchestrate highly targeted Business Email Compromise (BEC) and spear-phishing campaigns with surgical precision. For example, an attacker could use the leak to identify a specific individual in a company’s finance department and then send them a fraudulent wire transfer request that appears to come directly from their CEO, using the names and titles from the database to make the scam perfectly credible.

Key Cybersecurity Insights

This alleged data sale presents several critical threats to businesses and individuals globally:

• A Goldmine for Business Email Compromise (BEC) and Spear-Phishing: This dataset is a dream come true for social engineers. The rich context—including names, job titles, departments, and seniority—allows attackers to bypass generic phishing tactics and launch highly believable, personalized attacks designed to trick specific employees into making fraudulent payments, revealing credentials, or deploying malware.
• API Abuse as a Critical Third-Party Risk Vector: The claim that the data was obtained via API abuse highlights a growing and critical security challenge. While APIs are essential for modern business, insecure or poorly monitored APIs can be exploited by attackers to exfiltrate massive amounts of data in a way that can be difficult to distinguish from legitimate traffic, representing a significant supply chain risk.
• Blurring of Personal and Professional Identities Increases Risk: The inclusion of both business and personal contact information (emails, mobile numbers) for millions of professionals creates a multi-faceted threat. Attackers are not limited to targeting employees within the corporate environment; they can now pivot to attack them on their personal devices and accounts, bypassing corporate security controls to conduct fraud or social engineering.

Mitigation Strategies

In response to this threat, all organizations must assume their employees’ data is compromised and take proactive defensive measures:

• Implement Urgent and Targeted Anti-Phishing and BEC Training: All organizations should conduct immediate, targeted security awareness training that specifically educates employees on the sophisticated BEC and spear-phishing tactics this data enables. This training must go beyond identifying bad links and should mandate processes for verifying high-risk financial requests (like wire transfers or changes in payment details) through a secondary, out-of-band channel (e.g., a direct phone call).
• Deploy Advanced Email Security and DMARC: Standard email filters are often insufficient to stop highly targeted BEC attacks that do not contain malware. Companies must deploy advanced email security solutions that use behavioral analysis and AI to detect anomalies, impersonation attempts, and other signs of social engineering. Implementing and enforcing DMARC, DKIM, and SPF is also an essential technical control to prevent direct spoofing of a company’s domain.
• Strengthen Vendor and API Security Governance: This incident underscores the critical importance of third-party risk management. Organizations must conduct rigorous security assessments of all vendors, especially data providers. Furthermore, internal security teams must implement a robust API security strategy for their own systems, including strict authentication, authorization, rate limiting, and anomaly detection to prevent abuse.

Secure Your Organization with Brinztech As a cybersecurity provider, we can protect your business from the threats discussed here. Contact us to learn more about our services.

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