CyberRota Analysis
AI-GeneratedOpenPLC_v3 is vulnerable to a heap-based buffer overflow in the getData() function, which allows authenticated attackers to exploit the /modbus endpoint by sending a crafted HTTP POST request with an oversized device_name value. This vulnerability can lead to heap corruption, causing a denial of service by crashing the PLC process control loop and enabling attackers to overwrite adjacent configuration fields. Organizations using OpenPLC_v3 should prioritize addressing this issue, especially if they rely on the affected version for critical process control operations, as no fix is anticipated and the upstream repository has been archived.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
Note: these links are listed for security research and verification purposes only.
Original NVD Description
OpenPLC_v3 contains a heap-based buffer overflow in the getData() function in webserver/core/modbus_master.cpp. getData() reads characters between two delimiters into a caller-supplied buffer with no size parameter and no bounds check. In parseConfig() the function is invoked with the 100-byte heap-allocated MB_device.dev_name field. An authenticated attacker with access to the OpenPLC web interface can send a crafted HTTP POST to the /modbus endpoint with an oversized device_name value; the value is persisted to mbconfig.cfg and parsed on load, overflowing dev_name and overwriting adjacent struct fields (protocol at offset 108, dev_address at offset 109, ip_port at offset 210). A 200-byte payload writes 100 bytes past the allocation. The result is heap corruption leading to runtime crash and denial of service of the PLC process control loop, with attacker-controlled overwrite of adjacent configuration fields. The upstream repository was archived on 2026-04-04 and no fix is expected; the vendor has confirmed the issue does not affect OpenPLC Runtime v4.