Quest Diagnostics Discloses Breach of Some Patient Records
WHO:
WTNH - Quest Diagnostics, a medical laboratory operator, reported a cyber breach affecting “certain patient records.”
ABC News - Quest Diagnostics said certain patient records were likely compromised; the number of patients and the specific records affected are unknown.
ABC News - The New Jersey-based company is working with external cybersecurity experts and notified federal law enforcement.
ABC News - In an earlier breach, data belonging to about 34,000 people was exposed; in a separate incident involving American Medical Collection Agency, personal information of about 11.9 million Quest patients was affected.
WHAT:
WTNH - Quest Diagnostics reported “unauthorized access” to its Quanum Lab Services Manager, a system used by certain clients to place test orders and receive results.
ABC News - Quest said the full scope of the breach remained under investigation.
ABC News - Quest said an earlier breach exposed data including lab results and contact information; a separate hack at American Medical Collection Agency affected other personal information belonging to about 11.9 million Quest patients.
ABC News - The article reports that an AI-assisted discovery identified vulnerabilities in PHP, a programming language described as vital to 70% of websites globally. Firms rushed to patch risks, and outages and limited service continued.
ABC News - Quest confirmed to The Associated Press that its breach was not related to the PHP issue.
WHERE:
ABC News - Quest Diagnostics is based in New Jersey.
WTNH - The report is datelined Chicago.
WHEN:
WTNH - Quest said it learned of the breach during the week described in the article.
ABC News - Quest said it discovered the hack on Wednesday and reported it in a Thursday regulatory filing.
ABC News - The company’s earlier breaches occurred in 2016 and 2019.
ABC News - The PHP vulnerabilities were discovered and prompted urgent patching during the week described in the article.
HOW:
ABC News - The breach involved unauthorized access to Quanum Lab Services Manager, where clients can place test orders and receive or look up results.
ABC News - Quest said it was responding with help from external cybersecurity experts and had notified federal law enforcement.
(UPDATED October 22, 2026 19:24 UTC)
Quest Diagnostics says unauthorized access to its Quanum Lab Services Manager may have compromised certain patient records. The New Jersey-based company learned of the breach during the week described in its filing, and the full scope remains under investigation. The system allows some clients to place lab test orders and receive or look up results. Quest says the number of patients affected and the specific records involved are not yet known. The company is working with outside cybersecurity experts and has notified federal law enforcement. Quest also says the breach was not connected to recently discovered vulnerabilities in PHP, which prompted urgent patching and some service disruptions. Earlier incidents exposed data belonging to about 34,000 people, while a separate hack at the American Medical Collection Agency affected personal information belonging to about 11.9 million Quest patients.