Quest Diagnostics confirms patient health data taken in Quanum lab system cyberattack

Quest Diagnostics confirmed that some patients' protected health information was taken in a cyberattack on its Quanum LSM lab test ordering system. The company learned of the unauthorized access on October 21, 2026, disclosed it in an 8-K filing, and said it notified law enforcement. It has not said which data categories were taken or how many patients are affected.