HD Home Depot Inc

Quest Diagnostics Inc. said it is investigating a breach of one of its web applications, by which the health records of 34,000 individuals were accessed.

The company said information was accessed by an unauthorized third party on Nov. 26 that included lab results and in some cases, phone numbers, but didn't include social security numbers, credit-card information, insurance or other financial information. The affected application is called MyQuest by Care360.

Quest said it is working with a cybersecurity firm to assist in the investigation and in further evaluating the company's systems. The company is notifying individuals affected by the breach by mail.

High-profile cyberattacks have hit companies such as Yahoo Inc., Home Depot Inc. and Target Corp. in recent years. In the health sector, Newkirk Products Inc., which provides ID cards for health-insurance plans, earlier this year disclosed a data breach that involved unauthorized access to a server containing member information. About 3.3 million members of insurance plans were affected.

Write to Tess Stynes at tess.stynes@wsj.com

(END) Dow Jones Newswires

December 12, 2016 18:35 ET (23:35 GMT)

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