OpenPLC Runtime v3 contains an authenticated arbitrary file write vulnerability in the legacy web UI program‑upload workflow. The application stores an attacker‑supplied filename (progfile) directly into the Programs.File database field and later uses this value as the destination path for an uploaded file without validating or restricting the path. Because Python os.path.join() honors attacker‑controlled absolute paths, an authenticated user can write arbitrary files anywhere writable by the OpenPLC webserver process. In the default build pipeline, all C++ source files within the OpenPLC runtime core directory are automatically compiled into the executable runtime binary. By writing a malicious .cpp file into this directory, an authenticated attacker can escalate the arbitrary file write into arbitrary native code execution when the operator triggers a normal program compilation and runtime start.

OpenPLC 3 through 64f9c11 has server.cpp Memory Corruption because a thread may access handleConnections arguments after the parent stack frame becomes unavailable.

OpenPLCV3 contains an arbitrary file upload vulnerability, which could be leveraged for malvertising or phishing campaigns.

A stack-based buffer overflow vulnerability exists in the OpenPLC Runtime EtherNet/IP parser functionality of OpenPLC v3 b4702061dc14d1024856f71b4543298d77007b88. A specially crafted EtherNet/IP request can lead to remote code execution. An attacker can send a series of EtherNet/IP requests to trigger this vulnerability.

OpenPLC 3 through 9cd8f1b allows XSS via an SVG document as a profile picture.

Command Injection in Open PLC Webserver v3 allows remote attackers to execute arbitrary code via the "Hardware Layer Code Box" component on the "/hardware" page of the application.

A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLCv2 and OpenPLCv3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.