This could very well be a simple bug where it's supopsed to XOR with some really random string generated on the server, but some replacement of a template string isn't happening which is why it XORs with RANDOM_STRING.

Of course this is only marginally better and should really have been caught, but there's a huge difference between saying that XORing 12 bytes with RANDOM_STRING is kick-ass DRM and actually having a kick-ass DRM infrastructure that then doesn't work right because of a bug.

If this was any really random looking string, I would be more inclined to assume that this was intentional. By the string being this token, I would guess it's a bug somewhere.

Remember. If RANDOM_STRING was truly random, unique per file and account and only transmitted from the server before playing, then this would be as good an encryption as any.