The source code for Team Fortress 2 has apparently been leaked, leading to hackers reportedly able to deliver malware through Remote Code Execution to other players. 

This leak was initially reported by @SteamDB on Twitter, with the source code in question dating back to 2017 and 2018, affecting Counter-Strike: Source and Team Fortress 2. According to a report on the issue from PCGamesN, several Team Fortress 2 server communities have advised players to avoid the game until further notice. 

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