Nium, Inc. Data Breach Exposes Social Security Numbers

On Dec. 10, 2025, global payments platform Nium, Inc. disclosed a data breach to the Massachusetts Attorney General’s office, impacting 13 individuals in the state. The breach involved unauthorized access to the company’s file system, which resulted in the download of certain customer information. The incident was first detected on Nov. 3, 2025, when Nium’s security teams identified suspicious access attempts targeting their file storage infrastructure.

Upon investigation, Nium determined that an old file from 2022 containing sensitive personal information was accessed. The exposed data included names, email addresses, physical addresses, phone numbers, Social Security numbers and dates of birth. All of these are considered personally identifiable information (PII); no protected health information (PHI) was involved. The affected file was stored in a system primarily used for technical system logs, not for storing personal information, which suggests the breach was limited in scope but involved highly sensitive data.

According to the Massachusetts disclosure, the breach was quickly contained after detection. There is no indication that account credentials or financial information were accessed. However, the exposure of Social Security numbers and other PII increases the risk of identity theft and phishing attempts for those affected.

Nium's response

Nium has notified affected individuals by email and is offering complimentary credit monitoring services. The company encourages those impacted to remain vigilant for phishing attempts, especially emails or messages that request verification of accounts or personal information. They also advise being alert to impersonation scams, as exposed PII could be used by malicious actors to pose as the affected individuals.

Affected customers are encouraged to contact Nium at help@instarem.com with any questions or concerns about the incident or to enroll in the offered credit monitoring service. This dedicated email address is monitored by senior management to ensure prompt responses.