A public utility in the U.S. suffered a compromise after attackers took advantage of a weak password security system.
The utility’s control system was accessible via Internet-facing hosts and used a simple password system, wrote the Industrial Control Systems Cyber Emergency Response Team (ICS-CERT) in a report on incidents covering the first quarter of this year.
The unidentified utility was vulnerable to a brute-force attack, where hackers try different combinations of passwords until they find the right one. An investigation showed the utility suffered an attack before.
“It was determined that the systems were likely exposed to numerous security threats, and previous intrusion activity was also identified,” ICS-CERT wrote in the report.
The U.S. government continues to warn critical infrastructure players like power and water plants they remain at risk of cyberattack, as many of their IT systems have not undergone an audit for vulnerabilities and configuration mistakes.
ICS-CERT warned it is easy for hackers using search engines such as Google and SHODAN to find Internet-connected control systems “that were not intended to be Internet facing.”
The report described a second cyberattack but did not give further details.
In that instance, an Internet-connected control system that operated a mechanical device ended up accessed by an attacker using a cellular modem. The access was through a SCADA (supervisory control and data acquisition) protocol, ICS-CERT said.
“The device was directly Internet accessible and was not protected by a firewall or authentication access controls,” ICS-CERT wrote.
The attacker appears to have struck at the wrong time as the device was undergoing scheduled maintenance and ended up disconnected from the control system.
In the first quarter of this year, ICS-CERT advised 20 energy, water, nuclear and transportation utilities on identifying vulnerabilities and how to improve their cyberdefenses, the report said.