Anti-virus company AVG warns that 90% of hacked or cracked games downloaded via torrent or file-sharing sites are infected with malware or malicious code. The prevalence of cracked games, key generators, patches, cheats and more indicates that this is a crime based, organised, crime based initiative. AVG suggests players only download official game patches and updates, and to use different account username and passwords for each of the accounts you use in games or online. For the biggest titles such as World of Warcraft or Minecraft, a similar FileCrop search reveals hundreds of hacks.
Source: https://thehackernews.com/2013/04/90-of-pirated-games-are-infected-with.html