Allegedly, source code for a March 2019 version of CS:GO has been leaked online. Valve has yet to comment on the files to confirm their authenticity, but assuming they are genuine, this would be the latest version of CS ever leaked online. A previous leak in 2020 provided a limited engine repository for a 2017 version that was shared with third-party developers and partners.
Nearly three years have passed since CS2 was released, directly replacing CS:GO and ushering in a new era for this popular tactical FPS game. The launch of CS2 upgraded the game to Valve's latest Source 2, while CS:GO ran on the Source engine. However, CS:GO can still be downloaded from the Steam store, although it is no longer listed and now relies on community servers.
Counter-Strike: Global Offensive source code leaked online
The source of this leak has yet to be confirmed, but the initial reaction is that it "looks real." The files are currently available for download on archive.org. The 2020 leak was confirmed as authentic by Valve not long after, so we are awaiting a similar response this time. The 2020 leak also included TF2 code, but this time we have only seen CS:GO.
Reportedly, this newly leaked March 2019 version also includes Danger Zone — a battle royale game mode that no longer exists as an official mode in CS 2. The previously leaked 2017 version dates from when the mode was still unfinished; its internal codename at the time was "survival", and it was released to the public as Danger Zone in December 2018.
Leaked related game files
It is worth noting that after CS:GO returned to Steam earlier this year, community servers still retain a considerable player base (according to SteamDB data). As of writing, the daily player count is around 5,000, which is actually more than Counter-Strike: Source has today, assuming these numbers are not inflated by bot accounts.
We'll have to wait and see whether modders can actually do anything with this leaked code, though news of the leak may raise concerns about potential exploits, cheats, or other malicious activity.