I’m seeking ways to bolster the security of my Ubuntu system by curbing the ability of users to capture screenshots. Given that I’m using the X11 desktop environment, I’m particularly interested in exploring any configuration options or third-party tools that can help enforce this restriction. Any insights, recommendations, or guidance on how to achieve this goal within a Linux environment would be immensely valuable. Thank you for your assistance!
2
Answers
In plain X11 there’s little you can do to prevent any client, which has access to an X server to take screenshots of the display contents.
What you can do is "jail" clients that you don’t trust into a
Xephyr
nested X server, which will also sandbox the clipboard and any other ICE interactions.Also the QubesOS ultra hardened Linux distribution did some work on implementing seamless X11 client separation, so that’s also worth looking at, how they’ve done it.
Yes, you can prevent a user from taking screenshots in Linux by limiting their access to specific applications or using tools that manage screen capture functionality. Here are several approaches you can take:
Restricting Access to Screen Capture Applications: You can change the user’s permissions to limit access to screenshot-taking applications like
gnome-screenshot
,shutter
, orscrot
. This can be accomplished by changing the file permissions or employing technologies such as AppArmor or SELinux to enforce the limits.Using Screen Capture Prevention Tools: There are tools available that can prevent or restrict screen capture functionality. For example,
xtrlock
can lock the screen and prevent screenshots while it’s active. You can also use tools likeNoScreenshots
orScreenWings
that aim to prevent screenshots.Disabling Screen Capture Hotkeys: You can edit the system settings to disable or change the hotkeys used to take screenshots. This makes it more difficult for a user to snap an unintentional screenshot.