• Attackers stole extensive personal and medical data from 3.8 million individuals from Unlimited Technology Systems
  • Breach source and methods remain unknown, with no group claiming responsibility
  • Stolen data poses major fraud risks, prompting free identity monitoring from Kroll

US healthcare organization Unlimited Technology Systems has revealed it suffered a cyberattack in which it lost a treasure trove of sensitive information belonging to millions of people.

The company recently made the information public and shared details with the US Department of Health and Human Services, noting that someone broke in on October 5, 2025 and within five days exfiltrated valuable data belonging to just over 3.8 million people.

The attacker stole people’s full names, Social Security numbers (SSN), dates of birth, emails and mailing addresses, phone numbers, demographic information, scans of driver’s licenses and other government IDs, insurance cards, intake forms, health insurance policy numbers, claims and benefits information, medical record numbers, dates of service, and diagnosis data.

Supply chain woes

The company did not say who the threat actors were, or if they demanded any ransom in exchange for deleting the data.

No hackers have claimed responsibility just yet, and we also don’t know how they managed to break in, as different groups have different methods.

ShinyHunters, for example, prefer calling their victims on the phone, pretending to be IT support and convincing their victims to give them access via remote management tools. Other groups might try to exploit vulnerabilities in routers, firewalls, and other hardware.

Whoever it was, they have a valuable data set in their possession. This kind of information can be sold on the black market or used in identity theft and wire fraud. To mitigate these risks, Unlimited Technology Systems is offering free identity monitoring services to affected individuals through Kroll.

Unlimited Technology Systems is a software company that provides financial technology for healthcare organizations. It works with around 4,500 clinics and 6,500 specialty healthcare providers in the US, processing north of $70 billion in net healthcare charges every year.

According to BleepingComputer, the company processes information on behalf of its clients, which means that the victims of this attack have no direct relationship with Unlimited and have probably not even heard of it.

Sead is a seasoned freelance journalist based in Sarajevo, Bosnia and Herzegovina. He writes about IT (cloud, IoT, 5G, VPN) and cybersecurity (ransomware, data breaches, laws and regulations). In his career, spanning more than a decade, he’s written for numerous media outlets, including Al Jazeera Balkans. He’s also held several modules on content writing for Represent Communications.