A critical out-of-bounds read vulnerability in legacy Circutor SGE-PLC1000 and SGE-PLC50 units poses a risk of unauthorized memory access by authenticated users.

The flaw resides in the DownloadFile function, which improperly processes a user-supplied parameter using atoi() before using it as an array index. An authenticated attacker can trigger an out-of-bounds read by providing a maliciously crafted parameter value that exceeds the defined memory limits.

The vulnerability carries a CVSS score of 7.5, indicating a high level of concern for industrial control environments. Successful exploitation could lead to unauthorized access to sensitive memory contents, potentially causing system instability or revealing information that aids in further attacks against the infrastructure. Given that these devices are legacy hardware, the risk of unpatched vulnerabilities is significantly elevated.

Immediate Action: As these units are discontinued, users should transition to supported hardware equivalents, specifically the GEDE EDC, as recommended by the vendor.

Proactive Monitoring: Implement network segmentation to restrict access to these legacy devices to only authorized personnel and monitor for anomalous traffic patterns directed at the device management interface.

Compensating Controls: Deploy an industrial-grade firewall or intrusion detection system to monitor and block unauthorized requests to the affected PLC units.

Public Exploit Available: No — exploit_available (false).

Due to the end-of-life status of the SGE-PLC1000 and SGE-PLC50 series, patching is not a viable long-term solution. Organizations currently utilizing these devices must prioritize a migration plan to current-generation hardware to eliminate this exposure. Until migration is complete, strict access controls and network isolation must be enforced to minimize the attack surface.