CVE-2026-20764 is an OS command injection vulnerability identified in Copeland XWEB 300D PRO devices, specifically affecting versions 1.12.1 and prior. The vulnerability arises from improper input validation of the device hostname configuration parameter. When an authenticated user inputs malicious data into the hostname field, this data is executed during the system setup process, leading to remote code execution (RCE) on the device. This flaw is classified under CWE-78 (Improper Neutralization of Special Elements used in an OS Command), indicating that the system fails to sanitize input that is passed to OS commands. The vulnerability requires the attacker to have authenticated access, which raises the attack complexity, but no user interaction beyond authentication is necessary. The CVSS v3.1 base score is 8.0, reflecting high severity with network attack vector, high privileges required, no user interaction, and impacts to confidentiality, integrity, and availability. The vulnerability’s scope is classified as changed, meaning the exploit can affect resources beyond the initially vulnerable component. No patches or exploits are currently publicly available, but the risk remains significant given the potential for full system compromise. The affected product is typically used in industrial or building automation contexts, where device integrity and availability are critical.

The impact of CVE-2026-20764 is substantial for organizations deploying Copeland XWEB 300D PRO devices, especially in industrial control systems, building management, or critical infrastructure environments. Successful exploitation allows an attacker to execute arbitrary commands remotely, potentially leading to complete device takeover. This can result in unauthorized control over system functions, data leakage, disruption of operations, or use of the device as a pivot point for lateral movement within a network. The compromise of such devices can degrade operational reliability, cause safety hazards, and lead to significant financial and reputational damage. Given the device’s role in managing environmental or operational parameters, attackers could manipulate system behavior to cause physical or operational harm. The requirement for authentication limits exposure but does not eliminate risk, as credential theft or insider threats could facilitate exploitation. The lack of known exploits in the wild suggests a window for proactive defense, but also means attackers may develop exploits soon after disclosure.

To mitigate CVE-2026-20764, organizations should implement the following specific actions: 1) Immediately restrict administrative access to the Copeland XWEB 300D PRO devices using network segmentation and strong authentication mechanisms such as multi-factor authentication (MFA). 2) Monitor and audit all configuration changes, especially hostname modifications, to detect suspicious or unauthorized inputs. 3) Employ strict input validation and sanitization controls where possible, including whitelisting allowed hostname characters and lengths. 4) Isolate affected devices from critical network segments to limit potential lateral movement if compromised. 5) Maintain up-to-date backups of device configurations and system states to enable rapid recovery. 6) Engage with the vendor for timely patches or firmware updates and apply them as soon as they become available. 7) Conduct regular vulnerability assessments and penetration testing focusing on device management interfaces. 8) Educate administrators on secure configuration practices and the risks of command injection vulnerabilities. These measures go beyond generic advice by focusing on access control, monitoring, and proactive configuration management tailored to the device’s operational context.