CVE-2023-4346

KNX Association KNX Protocol Connection Authorization Option 1 Overly Restrictive Account Lockout Mechanism Vulnerability

KNX Association KNX Protocol Connection Authorization Option 1

CVSS

7.5High

ExploitationExploited in the wildAdded to KEV 15 Jul 2026CISA KEV

Exploit odds (EPSS)1.29%Chance of exploitation activity in the next 30 days, higher than 70% of CVEs. Scored 23 Oct 2026FIRST EPSS

Fixed inNone listedNo source names a fixed version. Check the vendor advisory below

Federal deadline29 Jul 2026Remediation due date for US federal agenciesCISA KEV

CISA required actionApply 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. CISA KEV

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Timeline

29 Aug 2023, 19:38 UTCPublishedCVE List
15 Jul 2026Added to CISA KEVCISA KEV

Description

KNX Association KNX Protocol Connection Authorization Option 1 contains an overly restrictive account lockout mechanism vulnerability that could allow an attacker to purge all devices without additional security options enabled and set a BCU key to lock the device.

Text from CVE List

Affected versions 1

KNX Protocol Connection Authorization Option 1affected: version unspecifiedCVE List