https://www.theregister.co.uk/2019/08/22/steam_zeroday_valve/

A security bod angry at Valve's handling of bug reports has released a zero-day vulnerability affecting the games giant's flagship Steam app.

Russia-based bug hunter Vasily Kravets said that he was releasing details of the flaw, an elevation of privilege error, after a series of poor interactions with Valve and HackerOne led to him getting banned from the Valve bug bounty program.