Hackers with suspected ties to the Chinese government breached systems belonging to New York's Metropolitan Transportation Authority (MTA).
According to the New York Times, the attacks took place in April but have only now come to light. Hackers didn't breach any systems used to control train cars or access any employee or passenger data, but researchers believe they might have implanted a backdoor to allow future access.
Federal authorities, including the FBI, alerted the MTA, which is responsible for transportation in the Big Apple, on April 20. It's the largest network in the US, with over 15.3 million users around New York City. It also runs the MTA New York City Transit, MTA Bus, Long Island Railroad, Metro-North Railroad, and MTA Bridges and Tunnels.
"The MTA's existing multilayered security systems worked as designed, preventing spread of the attack," the agency's chief technology officer Rafail Portnoy told the Times. "We continue to strengthen these comprehensive systems and remain vigilant as cyber attacks are a growing global threat."
"The MTA quickly and aggressively responded to this attack, bringing on Mandiant, a leading cyber security firm, whose forensic audit found no evidence operational systems were impacted, no employee or customer information breached, no data loss, and no changes to our vital systems," he added.
The leaked MTA document outlined the breach, which was one of many incidents carried out by hacking groups tied to Beijing that targeted federal agencies, defense contractors, and financial institutions.
Over two days in the second week of April, two hacking groups, one said to be working on behalf of China, gained access via a flaw in Pulse Connect Secure, a legitimate remote access tool.
The hackers held access until April 20, when MTA discovered the attack. By then, hackers had compromised three of the MTA's 18 computer systems. It was then the MTA alerted federal authorities.
It is not known why hackers targeted the MTA. Those investigating the case said that China may be trying to obtain data on the transit network to gain an advantage in the international rail car market.
As a precaution, the MTA has made the 3,700 users on its systems change their passwords.
