In GL.iNET GL-AR300M routers with firmware 3.216 it is possible to inject arbitrary shell commands through the OpenVPN client file upload functionality.
https://github.com/RicheByte/exploitdbPro
https://github.com/cyberaz0r/GL.iNet-Multiple-Vulnerabilities
https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-50672
https://cyberaz0r.info/2023/11/glinet-multiple-vulnerabilities/