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Vol. 1 · Ed. 2026
CyberGlossary
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Entry № 097

BACnet

O que é BACnet?

BACnetA building-automation and HVAC protocol standardized as ASHRAE 135 / ISO 16484-5 — widely deployed in HVAC, lighting, fire-alarm, and access-control systems in commercial buildings, historically with very weak authentication.

BACnet (Building Automation and Control networks) is the dominant communications protocol in commercial building automation. It is standardized as ANSI/ASHRAE 135 and ISO 16484-5 and underlies HVAC, lighting, fire-alarm, energy-management, and access-control systems in office buildings, hospitals, schools, data centers, and large industrial campuses. BACnet defines a layered protocol with multiple data-link options (BACnet/IP over UDP/47808, BACnet MS/TP over RS-485, BACnet/SC over TLS, plus older Ethernet, ARCNET, and LonTalk variants) and an object-oriented model of services and objects (Analog Input/Output, Binary Input/Output, Schedule, Trend Log, etc.). Legacy BACnet/IP has essentially no authentication: any host on the BACnet network can issue Write Property requests, broadcast Who-Is and I-Am, or inject device-control messages. The newer BACnet Secure Connect (BACnet/SC, 2020) runs BACnet over TLS-secured WebSockets and is the recommended path forward. Real-world incidents (including a 2017 ransomware attack on a Finnish heating control system and the 2024 Lviv FrostyGoop case, conceptually similar) routinely abuse weak BACnet posture. Defensive practices include strict VLAN isolation of building-automation networks from IT and OT-NDR coverage tuned for BACnet anomalies.

● Exemplos

  1. 01

    A pen-tester maps a building's BACnet network with `Who-Is` discovery and demonstrates an unauthenticated `WriteProperty` overriding a chiller setpoint.

  2. 02

    A retrofit project migrates the building's BACnet/IP backbone to BACnet/SC over TLS, with mutual certificate authentication between controllers.

● Perguntas frequentes

O que é BACnet?

A building-automation and HVAC protocol standardized as ASHRAE 135 / ISO 16484-5 — widely deployed in HVAC, lighting, fire-alarm, and access-control systems in commercial buildings, historically with very weak authentication. Pertence à categoria OT / ICS / IoT da cibersegurança.

O que significa BACnet?

A building-automation and HVAC protocol standardized as ASHRAE 135 / ISO 16484-5 — widely deployed in HVAC, lighting, fire-alarm, and access-control systems in commercial buildings, historically with very weak authentication.

Como funciona BACnet?

BACnet (Building Automation and Control networks) is the dominant communications protocol in commercial building automation. It is standardized as ANSI/ASHRAE 135 and ISO 16484-5 and underlies HVAC, lighting, fire-alarm, energy-management, and access-control systems in office buildings, hospitals, schools, data centers, and large industrial campuses. BACnet defines a layered protocol with multiple data-link options (BACnet/IP over UDP/47808, BACnet MS/TP over RS-485, BACnet/SC over TLS, plus older Ethernet, ARCNET, and LonTalk variants) and an object-oriented model of services and objects (Analog Input/Output, Binary Input/Output, Schedule, Trend Log, etc.). Legacy BACnet/IP has essentially no authentication: any host on the BACnet network can issue Write Property requests, broadcast Who-Is and I-Am, or inject device-control messages. The newer BACnet Secure Connect (BACnet/SC, 2020) runs BACnet over TLS-secured WebSockets and is the recommended path forward. Real-world incidents (including a 2017 ransomware attack on a Finnish heating control system and the 2024 Lviv FrostyGoop case, conceptually similar) routinely abuse weak BACnet posture. Defensive practices include strict VLAN isolation of building-automation networks from IT and OT-NDR coverage tuned for BACnet anomalies.

Como se defender contra BACnet?

As defesas contra BACnet costumam combinar controles técnicos e práticas operacionais, conforme detalhado na definição acima.

Quais são outros nomes para BACnet?

Nomes alternativos comuns: ASHRAE 135, Building Automation Network.

● Termos relacionados