A breach of Harvard University’s Alumni Affairs and Development systems exposed information associated with 851,000 unique email addresses, according to Have I Been Pwned, a breach notification service that analyzed data leaked by the attackers. The incident was discovered by the university on November 18, 2025, and involved systems accessed earlier that month.
The compromised information included names, email addresses, dates of birth, phone numbers, physical addresses, social media profiles, event attendance records, donation details, and biographical information connected to fundraising and alumni engagement. Have I Been Pwned said the records related to alumni and donors, as well as parents and some faculty, staff, and students.
Harvard Vice President and University Chief Information Officer Klara Jelinkova said the affected systems did not contain Social Security numbers, passwords, payment card details, or financial information.
Harvard has not publicly attributed the intrusion to a specific group. The ShinyHunters extortion gang claimed responsibility, saying it stole more than one million records. After Harvard declined to pay a ransom, the attackers posted a 1.1GB archive of documents on their dark web leak site in early February.
Have I Been Pwned reported that its analysis found data relating to 850,500 accounts, while the dataset contained 851,000 unique email addresses. Harvard had not previously disclosed how many people were affected.
Princeton University and the University of Pennsylvania also disclosed data breaches in November 2025, and both said donor information had been accessed.
Sources: BleepingComputer.