Critical Command Injection Flaw Threatens Circutor SGE-PLC1000/SGE-PLC50 PLCs

Overview

This article provides a comprehensive analysis of CVE-2025-11787, a command injection vulnerability discovered in Circutor SGE-PLC1000 and SGE-PLC50 programmable logic controllers (PLCs). The vulnerability affects versions up to and including 9.0.2 and could allow a remote attacker to execute arbitrary commands on the affected device. Given the potential impact on industrial control systems (ICS) and critical infrastructure, this vulnerability warrants immediate attention and remediation.

Technical Details

CVE-2025-11787 stems from insufficient input validation in the GetDNS(), CheckPing(), and TraceRoute() functions of the Circutor SGE-PLC1000/SGE-PLC50 operating system. An attacker can exploit this flaw by injecting malicious commands into parameters passed to these functions. These functions likely execute system commands based on user-supplied input without proper sanitization, leading to command injection. The vulnerable functions are accessible via network communication, potentially enabling remote exploitation.

CVSS Analysis

Currently, the CVSS score for CVE-2025-11787 is N/A. This may be because the vulnerability assessment is still in progress. However, given the nature of command injection vulnerabilities in PLCs, a high CVSS score is anticipated. The ability to execute arbitrary commands can lead to complete system compromise, affecting availability, integrity, and confidentiality. We will update this section once a CVSS score is officially assigned.

Possible Impact

Successful exploitation of CVE-2025-11787 can have severe consequences, including:

• Complete System Compromise: Attackers can gain full control of the PLC, allowing them to modify configurations, install malware, and disrupt operations.
• Denial of Service (DoS): By executing commands that crash the PLC or consume excessive resources, attackers can render the device unusable.
• Data Theft: Sensitive data stored on the PLC, such as configuration files or process data, can be accessed and exfiltrated.
• Process Manipulation: Attackers can alter the PLC’s logic, causing it to control connected industrial equipment in unintended or malicious ways, leading to equipment damage, product defects, or even safety hazards.

Mitigation and Patch Steps

Until an official patch is released by Circutor, the following mitigation steps are recommended:

• Network Segmentation: Isolate the affected PLCs on a separate network segment with strict access control policies.
• Firewall Protection: Implement firewall rules to restrict network access to the PLC only to authorized personnel and systems. Specifically, monitor and filter traffic to the ports used by the GetDNS(), CheckPing() and TraceRoute() functions if possible.
• Input Validation (If Possible): If the PLC’s configuration allows, implement stricter input validation on the parameters passed to the vulnerable functions. This might be possible through internal configuration tools, but proceed with caution as incorrect changes may disable the PLC.
• Monitor PLC Activity: Implement intrusion detection systems (IDS) to monitor PLC network traffic and system logs for suspicious activity.
• Contact Circutor Support: Reach out to Circutor support for the latest information on patches and mitigation strategies.
• Apply the Patch: Once Circutor releases a patch, apply it immediately to all affected SGE-PLC1000 and SGE-PLC50 devices.

References

INCIBE-CERT Advisory – Multiple Vulnerabilities in Circutor Products

Note: Please refer to Circutor’s official website for firmware updates and security advisories related to this vulnerability.