CVE-2026-44090 in CHARX SEC-3150
Summary
by MITRE • 07/30/2026
Due to missing authentication, an unauthenticated remote attacker may access the MQTT broker, which is only protected from external access by a firewall. This may lead to the device being fully compromised.
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Analysis
by VulDB Data Team • 07/30/2026
This vulnerability represents a critical security flaw in IoT device architecture where proper authentication mechanisms have been completely omitted from the MQTT broker implementation. The absence of authentication creates an unauthenticated access point that allows remote attackers to establish connections directly to the message broker without any credential verification. This fundamental weakness stems from poor security design principles and violates core security concepts outlined in cwe-305 authentication bypass vulnerabilities. The attack vector is particularly dangerous because it enables adversaries to gain direct access to the messaging infrastructure that typically handles sensitive communications between devices, applications, and backend systems. When an MQTT broker lacks proper authentication, attackers can not only read messages but also publish malicious payloads, subscribe to unauthorized topics, and potentially disrupt the entire communication ecosystem. The reliance on firewall protection alone creates a false sense of security since network-level controls can be bypassed through various means including IP address spoofing, port scanning, or exploitation of other network vulnerabilities.
The operational impact of this vulnerability extends far beyond simple unauthorized access as it essentially provides attackers with a foothold that can lead to complete device compromise. Once connected to the MQTT broker, an attacker can monitor all communications flowing through the system and potentially manipulate data flows in real-time. This capability allows for sophisticated attacks such as man-in-the-middle operations, data exfiltration, or even command injection into connected devices. The vulnerability directly maps to attack techniques described in the mitre att&ck framework under initial access and execution phases, particularly leveraging network service scanning and remote services exploitation tactics. From a compliance perspective, this flaw violates industry standards including iso 27001 security controls and nist cybersecurity framework requirements for secure system design and implementation.
Organizations must implement comprehensive mitigation strategies to address this vulnerability effectively. The primary requirement is to immediately enforce robust authentication mechanisms at the MQTT broker level using username/password combinations, certificate-based authentication, or other strong credential verification methods. Access control lists should be implemented to restrict topic access based on user roles and device permissions, ensuring that only authorized entities can publish or subscribe to specific message topics. Network segmentation should complement these security measures rather than replace them, with proper firewall rules configured to limit access to the MQTT broker port only to trusted networks and IP addresses. Regular security audits and penetration testing should be conducted to identify similar authentication bypass vulnerabilities across the entire IoT ecosystem. Additionally, implementing encryption for all communications between clients and the broker using tls protocols will add an additional layer of protection against eavesdropping and man-in-the-middle attacks. The remediation process must also include establishing monitoring and alerting mechanisms to detect unauthorized access attempts and potential exploitation activities.