The City of Naperville, Illinois data breach
Incident readout
- Company
- The City of Naperville, Illinois
- Reported to
- New Hampshire Attorney General
- Filed
- July 14, 2025
- People affected
- Not stated in the filing
- Incident type in filing
- Not stated
- Our review
- Investigation Open
Was this a ransomware attack?
The filing does not say ransomware was involved. We do not label an incident ransomware unless the company’s report says so. Whatever the cause, the steps to protect yourself and the legal question are the same.
What we know
The City of Naperville, Illinois is a municipal government entity responsible for providing public services, maintaining infrastructure, and managing administrative records for its residents. In the course of these operations, the city typically collects and stores sensitive personal information, including government identification numbers, tax records, utility account details, and employment-related data for municipal staff. This data breach was officially reported to the New Hampshire Attorney General in 2025, confirming that unauthorized access to certain systems occurred. If you have received a formal data breach notification letter, it indicates that your personal information may have been involved in this incident. This notification is intended to provide you with transparency regarding the event and guidance on the necessary steps to protect your identity and financial security.
See every breach reported in New Hampshire or read what to do after a ransomware attack.
Other breaches reported in New Hampshire
- Janome America, Inc.New Hampshire Attorney General · Filed July 31, 2026Count not stated
- Sullivan Environmental ServicesNew Hampshire Attorney General · Filed July 31, 2026Count not stated
- City of New Britain, Inc.New Hampshire Attorney General · Filed July 30, 2026Count not stated
- New Hampshire Housing Yardi’s RentCafeNew Hampshire Attorney General · Filed July 30, 2026Count not stated
- Pocket FMNew Hampshire Attorney General · Filed July 30, 2026Count not stated
- Werth Wealth Management, LLCNew Hampshire Attorney General · Filed July 29, 2026Count not stated
Attorney advertising. This page reflects a public regulator filing; it does not mean a lawsuit has been filed or that the company did anything unlawful. Submitting a review request does not create an attorney-client relationship.