According to a report by foreign media GTA Focal, the source code of GTA5 has been leaked on Discord, with a total file size of about 4GB, including a large number of files, concepts and reference images from the RAGE engine, such as the early map of San Andreas in GTA5. Surprisingly, the file even includes the unreleased GTA6 Python script files and the Bully 2 files, though this part seems small at the moment and probably doesn't make much sense.
The source code is not entirely new, it stems from the 2022 GTA 6 leak, when hackers also obtained the source code for GTA5 and have been looking to sell it ever since.
The game source code is the underlying set of instructions written in a programming language and is the foundation that makes up the game. It contains the logic, algorithms, and functions that define the game's operations. For these reasons, the source code must be kept strictly confidential in order to protect intellectual property and prevent unauthorized copying or modification of the game.