There is no interception and manipulation of a download going on, at least regarding the botnet the article suggests, it came from knowingly downloading and ins

There is no interception and manipulation of a download going on, at least regarding the botnet the article suggests, it came from knowingly downloading and installing pirated software. The checksum idea is to get the checksum from the official source and to apply it to the pirated download, but then the pirated download is surely modified anyway, so this wouldn't work.