CVE-2025-36754 is an authentication bypass vulnerability classified under CWE-290 affecting the Growatt ShineLan-X solar inverter web interface, specifically version 3.6.0.0. The root cause is the absence of proper authentication mechanisms such as session tokens or credential checks on the device’s web interface. This allows an attacker with low privileges and local network access to craft POST requests that modify device settings without authentication. One critical setting that can be altered is the domain name resolution address, which can be pointed to an attacker-controlled server. This manipulation can facilitate man-in-the-middle (MitM) attacks by redirecting legitimate device traffic to malicious endpoints, potentially compromising confidentiality and integrity of communications. The vulnerability has a CVSS 4.0 score of 9.3, reflecting its critical severity due to high impact on confidentiality, integrity, and availability, ease of exploitation without user interaction, and the ability to affect multiple security properties. While no exploits are currently known in the wild, the flaw’s nature and the critical role of solar inverters in energy infrastructure make it a significant threat. The lack of authentication also means that even low-privileged attackers on the local network can exploit this vulnerability, increasing the attack surface. The vulnerability was publicly disclosed in December 2025, with no patches currently available, emphasizing the need for immediate compensating controls.

For European organizations, the impact of this vulnerability is substantial, particularly for those relying on Growatt ShineLan-X devices in their solar energy infrastructure. Successful exploitation can lead to unauthorized configuration changes, enabling attackers to redirect device communications to malicious servers. This can result in interception or manipulation of sensitive operational data, disruption of energy production monitoring, and potential sabotage of energy management systems. The integrity and availability of solar inverter operations could be compromised, affecting energy supply reliability. Additionally, the vulnerability could be leveraged as a foothold for broader network intrusion or lateral movement within critical infrastructure environments. Given the increasing reliance on renewable energy sources in Europe, such disruptions could have cascading effects on energy grids and compliance with regulatory standards. The vulnerability’s ease of exploitation without user interaction and low privilege requirements further exacerbate the risk, especially in environments with inadequate network segmentation or device access controls.

Immediate mitigation steps include restricting network access to the ShineLan-X web interface by implementing strict firewall rules and network segmentation to limit device exposure to trusted management networks only. Organizations should monitor network traffic for unusual DNS queries or configuration changes indicative of exploitation attempts. Deploying intrusion detection systems (IDS) or anomaly detection tailored to detect unauthorized POST requests to the device’s web interface can provide early warning. Until an official patch is released, consider disabling remote management features if feasible. Employ network-level DNS filtering or DNS security extensions (DNSSEC) to prevent redirection to malicious DNS servers. Regularly audit device configurations and logs to detect unauthorized changes promptly. Engage with the vendor for patch timelines and apply updates immediately upon release. Additionally, incorporate this vulnerability into incident response plans and conduct staff training on recognizing signs of compromise related to this issue.