Hospital operator Community Health Systems said a cyberattack took information on more than 4 million patients from its computer network earlier this year, according to Reuters.
The Franklin, Tennessee, company said Monday that no medical or credit card records were taken in the attack, which may have happened in April and June, but Community said the attack did bypass its security systems to take patient names, addresses, birthdates, and phone and Social Security numbers, Reuters reported.
Security experts said the hacking group, known as "APT 18," may have links to the Chinese government, according to Reuters.
"APT 18" typically targets companies in the aerospace and defense, construction and engineering, technology, financial services and healthcare industry, said Charles Carmakal, managing director with FireEye Inc's Mandiant forensics unit, which led the investigation of the attack on Community Health in April and June, Reuters reported.
"They have fairly advanced techniques for breaking into organizations as well as maintaining access for fairly long periods of times without getting detected," he said, according to Reuters.
The hospital operator said it believes the attack came from a group in China that used sophisticated malware and technology to get the information, according to Reuters.
Community Health has since removed the malware from its system and finalized "other remediation efforts" to prevent future attacks, Reuters reported.
The information that was taken came from patients who were referred to or received care from doctors tied to the company over the past five years, according to Reuters.
Community Health Systems Inc. is notifying patients affected by the attack and offering them identity theft protection services, Reuters reported. The company owns, leases or operates 206 hospitals in 29 states.
The attack follows other high-profile data security problems that have hit retailers like the e-commerce site eBay and Target, according to Reuters. Last year, hackers stole from Target about 40 million debit and credit card numbers and personal information for 70 million people.
Shares of Community Health climbed 38 cents to $51.38 late Monday morning, while broader trading indexes also rose less than 1 percent, Reuters reported.
