An unauthenticated remote attacker can post a malicious ID to the MQTT Broker, which results in the creation of a new configuration entry in the system configuration. This flaw, identified as CWE‑501, can lead to integrity and availability loss by allowing the attacker to alter system settings without authorization.

The vulnerability affects Phoenix Contact products, specifically the CHARX SEC‑3000, CHARX SEC‑3050, CHARX SEC‑3100, and CHARX SEC‑3150 series. No specific product versions are listed in the data, so all current releases within these model families are potentially impacted unless later updates have mitigated the issue.

The CVSS score of 8.8 indicates a high severity, and the EPSS score of less than 1% shows low likelihood of exploitation at present. The attack vector is remote and does not require authentication, making any exposed MQTT broker a potential attack surface. While the vulnerability is not yet listed in CISA’s KEV catalog, the combination of high CVSS and remote unauthenticated access warrants taking preventive measures promptly.