[Gander5739]

When you download the torrent file, you're trusting that the provider of the torrent file, anna's archive in this case, is giving you legitimate files. Although I'm not sure how you would disguise undesirable files like viruses as ebooks; the file format would be a giveaway.

[DauntingPear7]

Malformed files that are designed to exploit known (or unknown) parsing vulnerabilities in whatever ebook reading software