A hacker is exploiting GitHub by distributing backdoored source code, specifically targeting hackers, gamers, and researchers. The malicious repositories, linked to the publisher "ischhfd83," deploy hidden backdoors through various means, leading to the installation of remote access trojans and info-stealers, which pose significant risks to users who compile the code. Sophos researchers warn of the sophisticated multi-step infection process that follows the download of these trojanized files.