hackerrank.com Domain Breach Exposure Report

The telemetry indicates a significant exposure event impacting hackerrank.com, with a risk score of 100. The primary concern stems from 752,430 historical data breaches and 138,880 active infostealer logs, affecting nearly 890,404 client accounts. Employee accounts also show a notable presence of 906 compromised records. The timeline reveals a surge in client and employee compromise events starting in late 2025 and peaking in early to mid-2026, with specific spikes in January, March, April, and June 2026. Malware families like LummaC2, Vidar, and Rhadamanthys are frequently observed, suggesting sophisticated credential harvesting operations. The overwhelming majority of leaked data originates from "Combolist sources," indicating a widespread reuse of compromised credentials. The targeted services are predominantly related to hackerrank.com's authentication endpoints, including signup and login pages. The geographical breakdown shows a concentration of affected users in India. Given the nature of the compromised data and the targeted services, the priority should be on immediate credential reset for all affected users, enhanced monitoring for suspicious login activity, and a review of authentication and data protection mechanisms on hackerrank.com.