mufg.jp Domain Breach Exposure Report

The domain mufg.jp has experienced a significant number of data breach and infostealer events over the past year, totaling over 114,000 incidents. A substantial portion of these events, approximately 73%, are classified as historical data breaches, while 26.7% are active infostealer logs. The timeline indicates a surge in employee-related events in January 2026, with nearly 1,500 incidents, and a notable increase in client-related events in March 2026, exceeding 33,000. Malware analysis shows LummaC2 as the predominant family, accounting for 43.1% of identified threats, followed by Rhadamanthys and Redline. Targeted services include direct banking portals like direct.bk.mufg.jp and entry points for online banking. The majority of data breach events originate from combolist sources, suggesting credential stuffing attacks. The high volume of data breaches and active infostealer logs, coupled with the targeting of critical banking services and a significant number of employee and client records exposed, indicates a high-risk exposure. The prevalence of LummaC2, a known infostealer, further elevates the risk of sensitive data compromise. Prioritization should focus on immediate remediation of identified vulnerabilities, enhanced credential security measures, and comprehensive monitoring of direct banking and online entry points. Given the nature of the targeted services and the domain, the primary focus should be on preventing further credential compromise and protecting client and employee data.