Almost certainly so. Decap the chip, pull the flash contents out to get the key, etc, flash a new backdoored chip, you're done. Hobbyists have been decapping ch

Almost certainly so. Decap the chip, pull the flash contents out to get the key, etc, flash a new backdoored chip, you're done. Hobbyists have been decapping chips and pulling flash for a while, so this is certainly not beyond the abilities of the NSA/CIA/etc. You wouldn't need the exact same make of chip, just one that presents itself as the same.