Lab testing giant Quest Diagnostics confirms patients’ personal and health data was compromised during breach

Medical lab testing giant Quest Diagnostics has confirmed a cyberattack and data breach affecting an as-yet unspecified amount of sensitive patient information stored in its systems, according to a legally required disclosure with U.S. regulators. Quest said in an 8-K filing with the U.S. Securities and Exchange Commission that it learned of a cyberattack on Wednesday targeting one of its lab testing systems, Quanum, which allows doctor’s offices, hospitals, and healthcare practices to request lab tests for patients while also handling billing.

Published 23-Oct-2026 16:20 UTC · First seen 23-Oct-2026 16:19 UTC

Sources

• TechCrunch · 23-Oct-2026