Sniffing OTA Updates out of the air

A colleague told me:

1. It is very simple to sniff an over-the-air update out of the air and steal the file. The file could then be used to program an exact copy of the device. For example, one could steal Tesla's AI driving software via this method.
2. The file generally is a .hex file and cannot be de-compiled to see the actual code and modify it.

Neither of us being cyber experts, I am wondering if either of …

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