Quest Diagnostics Confirms Hack on Quanum
The breach affects a system used by 500,000 clinicians to order lab tests, with patient records confirmed stolen.
By Aiko Soto ·
About 500,000 clinicians use the Quanum platform to order lab tests and handle billing across North America. Quest Diagnostics confirmed today that hackers accessed this system and stole patient records. The company disclosed the incident in an 8-K filing with the Securities and Exchange Commission. It stated it became aware of the attack on Wednesday. Quest did not specify how much data was affected or when the breach began.
Quanum serves as a core infrastructure for doctors' offices, hospitals, and other healthcare practices. The platform holds large volumes of patient health records, diagnostic data, and billing information. In a security notice, Quest said some patients' protected health information was taken. This included personal information and patient records. The company is still determining which specific data types were stolen. The notice page on its website carries noindex code, which prevents search engines from listing the page.
Quest has not said whether a hacking group has contacted it with demands. It has not specified if a ransom payment is being requested. Amanda Rivera, a Quest spokesperson, did not answer questions from TechCrunch and pointed to the security notice instead. The company said it has notified law enforcement and is investigating the incident.
The scale of the exposure could be considerable. Quest materials state that Quanum is used by thousands of locations. A 2026 case study on Quest's website describes a single health system with more than 6 million patients. That system holds hundreds of millions of related medical documents and charts. It is unclear how many records the Quanum system stores in total.
This is the latest in a series of major cyber incidents hitting the healthcare sector this year. In March, an attack led to the mass wiping of employee devices at medical technology maker Stryker. In August, a hack at medical implant manufacturer Boston Scientific forced its network offline for weeks. The company called that a global disruption to operations. Separate hacks this year also led to large breaches at medical recordkeeping company CareCloud, Scotland-based health tech provider Craneware, and U.S. pharmaceutical distributor McKesson.
This is Quest's second known major data breach in a decade. In 2019, the company lost 11.9 million patient records in a cyberattack on a third-party billing company. Quest has not provided a timeline for restoring full service or for notifying affected patients. The company continues to work out the details of what was stolen.
