Techniques for providing secure modification of manufacturer usage description (MUD) files based on device applications are provided. In one embodiment, a method for secure modification of MUD files may include obtaining a request for one or more applications from a device. The method also includes providing to the device the one or more applications and a certification that includes an updated MUD identifier determined based on the one or more applications requested. The updated MUD identifier is associated with a concatenated MUD file that comprises individual MUD file portions for each of the one or more applications requested. The device is configured to request an updated device identifier using the certification. The updated device identifier includes the updated MUD identifier that is associated with the concatenated MUD file.