Hackers have installed ransomware on systems of a natural gas compression facility in the United States, affecting the operational technology (OT) network, including human-machine interfaces (HMIs), data historians, and polling servers.
The Cybersecurity and Infrastructure Security Agency (CISA) offered details of the attack in an effort to inform other organizations about the danger of such intrustions and mitigation techniques.
In this case, a human served as the entry point for the hackers. Someone fell for a phishing email that contained a link that triggered the installation of malware. After the hackers had access to the network, infecting it with ransomware was easy.
While the attack on the natural gas compression facility could inflict a lot of damage, the hackers lacked access to programmable logic controllers (PLCs), so the company didn’t lose control of the actual operation.
This was one of the more fortunate cases, where the organization had quick access to backups, and restoration only took a couple of days.
“The victim’s existing emergency response plan focused on threats to physical safety and not cyber incidents,” says the advisory. “Although the plan called for a full emergency declaration and immediate shutdown, the victim judged the operational impact of the incident as less severe than those anticipated by the plan and decided to implement limited emergency response measures.”
Mitigation measures recommended by CISA include network segmentation, multi-factor authentication, data backups, specific Account Use Policies and Users Account control, spam filters, endpoint protection, disabling office macro scripts, and keeping software up to date. All of these are just the basic protections any company and organization should employ.
The CISA advisory doesn’t say what type of ransomware was used, how much ransom was requested, or name the hackers, but Ryuk and Sodinokibi have been used in the past on industrial systems.