The CVE-2025-36752 vulnerability concerns the Growatt ShineLan-X communication dongle, a device used primarily in solar energy systems to facilitate communication and monitoring. The vulnerability arises from the presence of an undocumented backup account embedded within the device firmware, which uses hard-coded credentials (CWE-798). These credentials are not publicly documented, effectively serving as a backdoor that grants attackers significant access privileges, including the ability to access the Setting Center of the device. This level of access allows an attacker to alter device configurations, potentially disrupt operations, or pivot to other parts of the network. The vulnerability affects version 3.6.0.0 of the ShineLan-X dongle. The CVSS 4.0 score of 9.4 reflects the critical nature of this flaw, with an attack vector classified as adjacent network (AV:A), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The impact on confidentiality, integrity, and availability is high, and the scope is high, meaning exploitation can affect components beyond the vulnerable device itself. No patches or fixes have been released at the time of publication, and no known exploits have been observed in the wild. The vulnerability was reserved in April 2025 and published in December 2025. Given the role of ShineLan-X dongles in solar energy infrastructure, exploitation could have serious operational and security consequences.

For European organizations, particularly those involved in renewable energy and solar power installations, this vulnerability poses a significant threat. Unauthorized access to the ShineLan-X dongle could allow attackers to manipulate device settings, disrupt energy monitoring and management, and potentially cause operational downtime or damage. This could lead to financial losses, regulatory non-compliance, and reputational damage. Furthermore, since these devices often form part of critical infrastructure, exploitation could have cascading effects on energy distribution and grid stability. The high severity and ease of exploitation without authentication or user interaction increase the risk of widespread compromise. Additionally, attackers could leverage this backdoor to move laterally within networks, targeting other connected systems. The lack of available patches means organizations must rely on compensating controls to mitigate risk in the short term.

1. Immediately segment networks to isolate ShineLan-X dongles from critical systems and limit access to trusted management networks only. 2. Implement strict network access controls and monitoring to detect unusual traffic patterns or unauthorized access attempts targeting the dongles. 3. Engage with Growatt to obtain information on planned patches or firmware updates and apply them promptly once available. 4. Conduct thorough inventory and asset management to identify all ShineLan-X devices in use and verify their firmware versions. 5. Employ intrusion detection and prevention systems (IDS/IPS) tuned to detect exploitation attempts related to this vulnerability. 6. Consider deploying compensating controls such as VPNs or encrypted tunnels for device communication to reduce exposure. 7. Train operational technology (OT) and IT security teams on the risks associated with hard-coded credentials and backdoors. 8. Develop incident response plans specific to potential exploitation scenarios involving these devices. 9. Where possible, replace vulnerable devices with alternatives that do not contain hard-coded credentials. 10. Regularly review and update security policies governing IoT and OT device management.