CVE-2023-4346

CVE Enrichment

CVSS: 7.5 HIGH
EPSS: 1.29%
EPSS Percentile: 69.54%
CISA KEV: YES — Known Exploited Vulnerability

Description

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.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: ics-cert@hq.dhs.gov
Published: 30-Aug-2023 03:15
Last Modified: 16-Jul-2026 12:16
EPSS Date: 2026-10-12
CWE: CWE-645

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:N /
                            I:N /
                            A:H

CISA KEV Details

Date Added: 2026-07-15
Remediation Due: 2026-07-29
Known Ransomware Campaign Use: Unknown
Required Action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Notes: https://www.cisa.gov/news-events/ics-advisories/icsa-23-236-01 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2023-4346

Affected Products / Versions

knx / connection_authorization
Version / affected range: -
cpe:2.3:a:knx:connection_authorization:-:*:*:*:*:*:*:*

References

Last enrichment sync: 13-Oct-2026 03:15
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (1)

CVE-2023-4346 Recorded Future Identifies 85 High-Impact Vulnerabilities in July, Many Actively Exploited

CVE (80)

Malware (4)

Threat Actors (8)

Vendors (25)

Products (70)

Tools (1)

Countries (1)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.