ABB Cylon FLXeon 9.3.5 (variant.js) Unauthenticated System Information Disclosure
Title: ABB Cylon FLXeon 9.3.5 (variant.js) Unauthenticated System Information Disclosure
Advisory ID: ZSL-2025-5937
Type: Local/Remote
Impact: Exposure of System Information, Exposure of Sensitive Information
Risk: (4/5)
Release Date: 21.05.2025
The FLXeon Controller Series uses BACnet/IP standards to deliver unprecedented connectivity and open integration for your building automation systems. It's scalable, and modular, allowing you to control a diverse range of HVAC functions.
CBX Series (FLX Series)
CBT Series
CBV Series
Firmware: <=9.3.5
Linux Kernel 4.15.13
NodeJS/8.4.0
Express
[22.04.2024] Vendor contacted.
[22.04.2024] Vendor responds.
[02.05.2024] Working with the vendor.
[20.05.2025] No response from the vendor.
[21.05.2025] Public security advisory released.
Web: https://www.zeroscience.mk
e-mail: [email protected]
Advisory ID: ZSL-2025-5937
Type: Local/Remote
Impact: Exposure of System Information, Exposure of Sensitive Information
Risk: (4/5)
Release Date: 21.05.2025
Summary
BACnet® Smart Building Controllers. ABB's BACnet portfolio features a series of BACnet® IP and BACnet MS/TP field controllers for ASPECT® and INTEGRA™ building management solutions. ABB BACnet controllers are designed for intelligent control of HVAC equipment such as central plant, boilers, chillers, cooling towers, heat pump systems, air handling units (constant volume, variable air volume, and multi-zone), rooftop units, electrical systems such as lighting control, variable frequency drives and metering.The FLXeon Controller Series uses BACnet/IP standards to deliver unprecedented connectivity and open integration for your building automation systems. It's scalable, and modular, allowing you to control a diverse range of HVAC functions.
Description
The ABB Cylon FLXeon BACnet controller's /api/variant endpoint exposes sensitive system information, including the internal IP address, MAC address, device model, and build type, without requiring authentication. The get() function gathers network interface data using the os.networkInterfaces() API and returns it in the HTTP response, potentially allowing unauthenticated clients to fingerprint internal infrastructure and gain insight into the device's network configuration and hardware characteristics.Vendor
ABB Ltd. - https://www.global.abbAffected Version
FLXeon Series (FBXi Series, FBTi Series, FBVi Series)CBX Series (FLX Series)
CBT Series
CBV Series
Firmware: <=9.3.5
Tested On
Linux Kernel 5.4.27Linux Kernel 4.15.13
NodeJS/8.4.0
Express
Vendor Status
[21.04.2024] Vulnerability discovered.[22.04.2024] Vendor contacted.
[22.04.2024] Vendor responds.
[02.05.2024] Working with the vendor.
[20.05.2025] No response from the vendor.
[21.05.2025] Public security advisory released.
PoC
abb_flxeon_ip.txtCredits
Vulnerability discovered by Gjoko Krstic - <[email protected]>References
[1] https://packetstorm.news/files/id/193671/Changelog
[21.05.2025] - Initial releaseContact
Zero Science LabWeb: https://www.zeroscience.mk
e-mail: [email protected]
