2015 6.7 Question

I have a truck that was tuned with a handheld tuner and they lost the tuner and it is stuck on a hot tune. If I have a completely stock file that matches the OS numbers is it safe to full flash the file and overwrite the handheld tuner changes without any issues? Also since this had a tuner already on it am I correct to assume that the RSA security has been patched?

If your Hot tune was for a deleted truck then you'll have several issues when flashing in a stock file.

And the RSA Bootloader is only for the 07-12 years, the 13+ require a actual ecm unlock, and since you have a modified file in, your ecm is unlocked and ready to accept another file