CVE-2025-29628 is a severe security vulnerability identified in the Gardyn Home Kit ecosystem, including its firmware, mobile application, and cloud API components. The core issue is the transmission of the Azure IoT Hub connection string over an unencrypted HTTP connection, which violates secure communication best practices and leads to improper enforcement of message integrity (CWE-924). This insecure transmission channel allows attackers positioned on the network path to perform man-in-the-middle (MitM) attacks, intercepting and potentially modifying the connection string. Since the connection string contains sensitive credentials used to authenticate and communicate with the Azure IoT Hub, an attacker who obtains it can impersonate the device, gain unauthorized access, or manipulate device operations. The vulnerability affects all versions prior to master.619 for firmware, versions before 2.11.0 for the mobile app, and versions before 2.12.2026 for the cloud API. The CVSS v3.1 base score of 9.4 indicates a critical severity, with attack vector network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and high impact on confidentiality and integrity (C:H/I:H) with low impact on availability (A:L). This vulnerability is particularly dangerous because it requires no authentication or user interaction, making exploitation straightforward if an attacker can intercept the network traffic. Although no known exploits have been reported in the wild, the widespread deployment of IoT devices and the sensitivity of the credentials involved make this a high-risk issue. The vulnerability also relates to CWE-200 (exposure of sensitive information) and CWE-77 (improper neutralization of special elements used in a command), indicating potential broader security implications if exploited. The root cause is a failure to use secure transport protocols such as HTTPS or TLS to protect critical credentials during transmission.

The impact of CVE-2025-29628 is significant for organizations and individuals using Gardyn Home Kit devices. Successful exploitation allows attackers to capture Azure IoT Hub connection strings, which can lead to unauthorized access to IoT devices and their cloud services. This compromises confidentiality by exposing sensitive credentials, integrity by enabling attackers to modify device commands or data, and availability to a lesser extent if attackers disrupt device operations. Compromised devices could be used as entry points into corporate or home networks, potentially facilitating lateral movement or further attacks. For enterprises relying on Gardyn devices for smart home or environmental monitoring, this could result in data breaches, operational disruption, and loss of trust. The vulnerability's ease of exploitation (no authentication or user interaction required) and network-based attack vector increase the risk of widespread abuse, especially in environments with untrusted or public networks. The lack of encryption also exposes users to passive eavesdropping and active manipulation attacks. Given the critical CVSS score, the threat is urgent and demands immediate attention to prevent potential large-scale compromise.

To mitigate CVE-2025-29628, organizations and users should: 1) Immediately update Gardyn Home Kit firmware to version master.619 or later, the mobile application to version 2.11.0 or later, and the cloud API to version 2.12.2026 or later once patches are released by the vendor. 2) Until patches are available, restrict network access to Gardyn devices by segmenting them on isolated VLANs or networks with strict firewall rules to limit exposure to untrusted networks. 3) Employ network-level encryption and VPNs to protect traffic between devices and cloud services, reducing the risk of interception. 4) Monitor network traffic for unusual patterns or unauthorized access attempts to detect potential exploitation. 5) Educate users about the risks of connecting devices over insecure or public Wi-Fi networks. 6) Work with Gardyn support to verify device integrity and confirm that updated versions enforce HTTPS/TLS for all credential transmissions. 7) Consider deploying intrusion detection/prevention systems (IDS/IPS) capable of identifying MitM attack signatures. These steps go beyond generic advice by focusing on network segmentation, traffic encryption, and proactive monitoring to reduce attack surface until vendor patches are fully deployed.