Overview
CVE-2025-0658 describes a significant vulnerability affecting Automated Logic and Carrier Zone Controllers. This vulnerability, exploitable through the BACnet protocol, can cause affected devices to crash. The device enters a fault state, and a subsequent packet after a reset can render the device permanently unresponsive, requiring a manual power cycle to restore functionality. This vulnerability poses a serious risk to building automation systems and critical infrastructure reliant on these controllers.
Technical Details
The vulnerability resides in the handling of malformed or specifically crafted BACnet packets. While the exact nature of the packet is not publicly available in this initial disclosure, it is understood that successful exploitation leads to a memory corruption or resource exhaustion condition within the Zone Controller’s firmware.
The sequence of events is critical: the first malicious packet triggers a device crash and subsequent reset. A second, potentially related, packet sent after the reset then causes a more severe failure that renders the device unresponsive until a manual power cycle. This two-stage failure mechanism makes it more difficult to recover from an attack through conventional remote management methods.
CVSS Analysis
As of the published date (2025-11-27), the CVSS score for CVE-2025-0658 is currently listed as “N/A”. This likely indicates that the score is still being calculated or hasn’t been officially assigned yet by the relevant authorities. However, given the potential for device crashes and permanent denial-of-service requiring physical intervention, the ultimate score is expected to be high, potentially in the “Critical” range once determined.
We will update this section as soon as CVSS information becomes available.
Possible Impact
The exploitation of CVE-2025-0658 can have severe consequences, including:
- Denial of Service (DoS): Devices can be rendered inoperable, disrupting building automation systems and potentially affecting critical infrastructure functions (e.g., HVAC, lighting, security systems).
- Loss of Control: Attackers could potentially disrupt the operation of systems controlled by the affected Zone Controllers, leading to environmental control failures and potential safety hazards.
- Physical Intervention Required: Recovery from a successful attack requires physical access to the device for a manual power cycle, leading to significant downtime and operational costs.
- Cascading Failures: In interconnected systems, the failure of one Zone Controller could potentially trigger cascading failures in other dependent systems.
Mitigation and Patch Steps
The primary mitigation strategy is to apply the official patch or firmware update provided by Automated Logic and Carrier as soon as it becomes available. Please refer to the official security advisory for detailed instructions and download links.
In the interim, consider the following temporary mitigation measures:
- Network Segmentation: Isolate the affected Zone Controllers on a separate network segment to limit the potential impact of a successful exploit.
- Access Control: Restrict network access to the Zone Controllers to only authorized devices and personnel.
- BACnet Security Hardening: Implement BACnet security best practices, such as disabling unused services, configuring strong passwords, and enabling BACnet/SC (Secure Connect) if supported.
- Intrusion Detection/Prevention Systems (IDS/IPS): Deploy network-based IDS/IPS solutions to detect and block malicious BACnet traffic. Monitor network traffic for unusual BACnet activity.
