Apollo.io Data Breach Exposes 1 Million B2B Contact Records

In June 2024, HEROIC analysts confirmed a significant data breach affecting Apollo.io, a U.S.-based AI-driven sales intelligence and engagement platform. The breach exposed 1,033,690 records containing professional and personal contact information for users of the platform. Apollo.io serves as a critical business tool for B2B sales teams worldwide, meaning this breach places not only individuals but entire organizations at risk of targeted attacks. The scale of exposure and the richness of the professional data involved make this one of the more consequential sales platform breaches in recent years.

Why This Is Dangerous

Over one million records from a sales intelligence platform represent a ready-made targeting list for sophisticated threat actors. Unlike generic credential dumps, this data includes professional context such as job titles and company affiliations, allowing attackers to craft extremely convincing business email compromise (BEC) attacks and spear-phishing campaigns. Victims may receive fraudulent emails that appear to come from known contacts or leadership within their organization. The combination of phone numbers and email addresses also enables vishing (voice phishing) attacks.

What Was Exposed

• Email Address
• Phone Number
• First Name
• Last Name

Why This Matters

The professional nature of the data exposed in this breach amplifies the threat significantly. Attackers with access to job titles and company affiliations can impersonate executives, vendors, or colleagues in phishing emails designed to trigger wire transfers or credential harvesting. Credential stuffing attacks using exposed email addresses can lead to account takeover (ATO) across dozens of platforms where victims reuse passwords. Identity theft and business fraud are both elevated risks when contact data of this depth is in criminal hands.

How Database Breaches Work

A database breach occurs when an unauthorized party gains access to a company's data storage systems. Attackers commonly exploit unpatched software vulnerabilities, use SQL injection against web-facing applications, compromise administrative credentials through phishing or brute force, or take advantage of misconfigured cloud storage. Once access is achieved, attackers extract large volumes of structured data. This data is then distributed through dark web marketplaces and hacking forums, where it is purchased by other threat actors for use in follow-on attacks.

Check If You Are Affected

HEROIC's free breach scanner checks your email address against a database of over 400 billion compromised records, including data from the Apollo.io breach. If your information was exposed, you will receive an immediate alert with actionable next steps to secure your accounts. Run a free scan at heroic.com to find out if your data is at risk.