Quest Diagnostics(DGX) - Get Report has announced that a hacker has obtained health data of 34,000 of its patients. 

The medical laboratory company, which provides quick blood draw and urine testing services to patients, announced after market's close Monday that the data breach had taken place. According to the announcement, the data obtained by the unknown hacker included the patients' name, date of birth, lab results, and in some cases, their telephone numbers. This data was obtained on Nov. 26. 

The patients impacted by this data breach have been notified via mail. Credit card information and Social Security numbers were not accessed in the hack. 

"When Quest Diagnostics discovered the intrusion, it immediately addressed the vulnerability," the company said in a statement. "Quest is taking steps to prevent similar incidents from happening in the future, and is working with a leading cybersecurity firm to assist in investigating and further evaluating the company's systems."

Quest has notified the authorities, and set up a hotline for patients affected. 

The company closed at $91.71 Monday, and hasn't moved in premarket trading yet. It's share price is up 35% in the past year.