---
title: "CVE-2023-4346: Overly Restrictive Account Lockout Mechanism | CubePath"
description: "KNX devices that use KNX Connection Authorization and support Option 1 are, depending on the implementation, vulnerable to being locked and users…"
language: en
source: https://cubepath.com/security/cve/CVE-2023-4346
---

# CVE-2023-4346: Overly Restrictive Account Lockout Mechanism | CubePath

## 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.

Official description from the CVE record, published by icscert. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-4346)

## Key data

### CVSS 3.1 High 7.5

Score published by icscert in the CVE record.

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

| Metric                 | Value     | What it means                                                                       |
| ---------------------- | --------- | ----------------------------------------------------------------------------------- |
| Attack vector          | Network   | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity      | Low       | No special conditions are needed. The attack can be repeated at will.               |
| Privileges required    | None      | No account or privileges are needed.                                                |
| User interaction       | None      | No action from any user is needed.                                                  |
| Scope                  | Unchanged | The impact stays within the vulnerable component.                                   |
| Confidentiality impact | None      | No effect on the secrecy of data.                                                   |
| Integrity impact       | None      | No effect on the trustworthiness of data.                                           |
| Availability impact    | High      | Serious or total effect on availability.                                            |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.01363 (1.4% probability)

Percentile

72.0%

Scores of

Nov 10, 2026

Model

v2026.06.15

### CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog

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

Added to the catalog

Jul 15, 2026

Federal due date

Jul 29, 2026

### CISA assessment as of Jul 15, 2026

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation

Recorded by CISA as active

Automatable

yes

Technical impact

partial

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-645](https://cwe.mitre.org/data/definitions/645.html) Overly Restrictive Account Lockout Mechanism

## Affected products

Products listed in the CVE record, as the CNA published them.

- KNX Protocol Connection Authorization Option 1

  - affected: 0

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [cisa.gov/news-events/ics-advisories/icsa-23-236-01](https://www.cisa.gov/news-events/ics-advisories/icsa-23-236-01) government-resource

## Timeline

1. ID reserved Aug 14, 2023
2. Record published Aug 29, 2023
3. Added to CISA KEV Jul 15, 2026
4. Record last updated Jul 16, 2026

## Look up another CVE

## About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

[Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection)

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 20:01 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)