> It's widely known that X11 has a problem with, for example, keyloggers. The issue is not that keyloggers are possible through security holes -- but keyloggers are trivial on X11, as they are part of normal operation and don't require exploits. It is one of the reasons why people push for Wayland.
Sorry, but did I miss news about a keylogger epidemic? On Linux?
In all seriousness, is this solving an actual problem or an imagined one?
And even assuming a 'Yes': A problem that isn't better solved elsewhere? How did the keylogger get access to the system and its desktop session? What else does it have access to?
Firejail discusses this briefly in their X11 guide:
The sandbox replaces the regular X11 server with Xpra or Xephyr server. This prevents X11 keyboard loggers and screenshot utilities from accessing the main X11 server.
It's not a common issue, but obviously a security concern to make it so easy for keyloggers to record your keypresses or screen. I currently prefer X11 to Wayland, and I'd love if this problem was possible to address without Firejail. I use Firejail for other sandboxing tasks, but sandboxing X11 is too impractical.
That's not an answer. Yes, I can run xev on my machine against my X session and see my keystrokes. It is not obvious that this is a problem. A more plausible angle would be that if an attacker compromises one application - say, a web browser - then they could keylog passwords. Of course, most people don't sandbox their browser so that's the least of their problems if it's compromised (ex. https://access.redhat.com/articles/1563163 let an attacker steal ssh keys).
Sorry, but did I miss news about a keylogger epidemic? On Linux?
In all seriousness, is this solving an actual problem or an imagined one?
And even assuming a 'Yes': A problem that isn't better solved elsewhere? How did the keylogger get access to the system and its desktop session? What else does it have access to?