Famous Apex Legends hacker gained access to computers of high-ranked esports players right when they were playing on a championship and streaming, and enabled cheats on their computers.

He claimed that it's possible due to security issues of Apex servers and the app itself. Technically, the app is gaining fairly high level of access to players' computers and he found a way to install any software remotely to any player's computer when this player is online in Apex.

Some security professionals doubt this specific way of injection and suggested that both players got their computers infected any other way (for example, via sponsorship deals malware).

But the same issue with remote access happened with Dark Souls 3 (and to fix this the whole game went offline for 6 months). Which let us to conclude: hacker's statement is possible.