I am doing some research about fport. I am working on a new LoRa/LoRaWAN YouTube tutorial about payload formatters and fports. I know that the fport value can be set programmaticaly (1-223) and the fport value is not encrypted. Lets assume a device transmits its sensor data and the fport value is set to 10. The message is received by both gateways A and B. Both gateways forwards the received message to the same public LoRaWAN network, for example TTN.
Lets assume gateway B is owned by a hacker. My question is: Can the hacker change the fport value from 10 to 5 at the gateway and than forward the package to the public LoRaWAN network?
If this is possible I have to mention this in my video, that fport should not be used for something critical or sensitive. I searched this forum, Google and the LoRaWAN 1.0.2 specification (https://lora-alliance.org/wp-content/uploads/2020/11/lorawan1_0_2-20161012_1398_1.pdf) but could not find ANY information about the subject.