KNX devices that use KNX Connection Authorization and support Option 1 are, depending on the implementation, vulnerable to being locked and users being unable to reset them to gain access to the device. The BCU key feature on the devices can be used to create a password for the device, but this password can often not be reset without entering the current password. If the device is configured to interface with a network, an attacker with access to that network could interface with the KNX installation, purge all devices without additional security options enabled, and set a BCU key, locking the device. Even if a device is not connected to a network, an attacker with physical access to the device could also exploit this vulnerability in the same way.

Advisories
Source ID Title
EUVD EUVD EUVD-2023-54211 KNX devices that use KNX Connection Authorization and support Option 1 are, depending on the implementation, vulnerable to being locked and users being unable to reset them to gain access to the device. The BCU key feature on the devices can be used to create a password for the device, but this password can often not be reset without entering the current password. If the device is configured to interface with a network, an attacker with access to that network could interface with the KNX installation, purge all devices without additional security options enabled, and set a BCU key, locking the device. Even if a device is not connected to a network, an attacker with physical access to the device could also exploit this vulnerability in the same way.
Fixes

Solution

No solution given by the vendor.


Workaround

The KNX Association recommends users always set the BCU Key in every KNX Project that is already finished and will be commissioned in the future. Handover the BCU Key as part of the Project Documentation to the Building Owner.

History

Tue, 01 Oct 2024 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: icscert

Published:

Updated: 2024-10-01T20:32:28.522Z

Reserved: 2023-08-14T22:14:58.101Z

Link: CVE-2023-4346

cve-icon Vulnrichment

Updated: 2024-08-02T07:24:04.770Z

cve-icon NVD

Status : Modified

Published: 2023-08-29T20:15:10.300

Modified: 2024-11-21T08:34:53.987

Link: CVE-2023-4346

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.