Johnson Controls iSTAR Ultra Vulnerabilities: 2025 Exposure of OT Systems
In December 2025, Johnson Controls publicly disclosed critical vulnerabilities (CVE-2025-43873 and CVE-2025-43874) affecting several versions of its iSTAR Ultra and Edge G2 door controllers used in building automation across critical infrastructure sectors worldwide. These OS Command Injection flaws, exploitable remotely with low attack complexity and minimal user interaction, could allow attackers to gain full control of vulnerable devices, modify firmware, and potentially disrupt or compromise secure building environments. The vulnerabilities were responsibly reported by Reid Wightman of Dragos, and patches have been made available for affected products. This incident highlights increasing threats targeting operational technology (OT) in critical sectors, as cybercriminals and nation-state actors leverage software supply chain and device-level weaknesses for initial access. The prevalence of command injection vulnerabilities, coupled with rising demands for segmentation and zero trust architectures, elevates the urgency for organizations to update OT and IoT assets and enforce proactive defense strategies.
Kill Chain