University of Pennsylvania – 623,750 breached accounts

In October 2025, the University of Pennsylvania was the victim of a data breach followed by a ransom demand, largely affecting its donor database. After the incident, the attackers sent inflammatory emails to some victims. The data was later published online in February 2026 and included 624k unique email addresses alongside names and physical addresses. For some donor records, additional personal information was exposed, including gender and date of birth. A small subset of records also contained religion, spouse name, estimated income and donation history.