A picture of a Tridium device running the Niagara AX framework. Tridium More than 20,000 Internet-connected devices sold by Honeywell are vulnerable to a hack that allows attackers to remotely seize control of building heating systems, elevators, and other industrial equipment and in some cases, cause them to malfunction. The hijacking vulnerability in Niagara AX-branded hardware and software sold by Honeywell's Tridium division was demonstrated at this week's Kaspersky Security Analyst Summit in San Juan, Puerto Rico.