CRC checks on challenges

Does anyone else think some sort of CRC check needs to be in place to make sure un-modded files for the current version of the game are being used for challenges (especially the survival challenges)?

A CRC might be too simple, as I think files could be padded with the right numbers to make it work?

You may be correct on that (even if it sounds like a lot work to pad each modified file).

It doesn’t have to be a CRC. Maybe it could just check the time stamp on the files or use some other mechanism to get the same results.