The security firm TrustedSec said in a blog post on Tuesday that a recent hack of the healthcare network Community Health Services was the result of an attack on the so-called “Heartbleed” vulnerability in OpenSSL. According to TrustedSec, attackers targeted vulnerable VPN (virtual private network) software from Juniper networks in a breach that affected an estimated 4.5 million patients. TrustedSec cited a “trusted and anonymous source close to the CHS investigation” in its blog post. It said attackers were able to glean user credentials from memory on a CHS Juniper device by exploiting the Heartbleed vulnerability. Those credentials were used to login via the VPN to CHS’s network, then move laterally to the servers containing the patient data. [Read more Security Ledger coverage of the Heartbleed vulnerability here.] A separate report by Bloomberg attributed the attack to hackers in China, though it did not provide any evidence linking the attackers to a specific Chinese […]