Block Screenshots on Casper

[technicholas]

Hello,

Is there a way you can block a student from taking screenshots on the mac?

[jacob_salmela]

You could make a custom config profile for disabling the keyboard shortcuts that allow screenshots: System Preferences > Keyboard > Keyboard Shortcuts > Screen Shots.

Or you could prevent /usr/bin/screencapture from running

[technicholas]

Thanks Jacob that makes since!

[mm2270]

You may want to also block the Grab.app. I don't know if it uses the command line screencapture binary to do its work, although maybe.

[kempt]

@ jacob_salmela
How exactly would I create this config profile? I know how to disable the keyboard shortcut, but I'm not clear as to how I would disable it in a profile.

[davidacland]

If you're already doing application whitelisting with the restrictions payload in a config profile then that would probably be the way to go.

Otherwise (with some testing) I would just remove the binary from the machines via a policy. You could grab a separate copy and store it in Casper so you can easily deploy it if you need to.

[kempt]

What is the actual name to disable in the Restrictions Payload?

[mm2270]

Something else that could help, but not exclusively (I would still implement the above solutions like creating Restricted Software items and Config Profiles, etc) is the following command run as the user. Maybe a script line run at login, or even a Config Profile payload to do this?

defaults write com.apple.screencapture location /private/var/
killall SystemUIServer

This sets the save location for screenshots to /private/var/ which can't be written to without admin authorization. When you try to do a screen shot, even when using an admin level account, you get an error in the Finder that the screenshot can't be saved to the location where they get stored (it doesn't mention the actual location)
This doesn't prevent throwing in the Control key to the key combo to store the capture in the clipboard though.

[bpavlov]

Obviously this is a technical question and you've gotten some good ones in that regard. However, if the end user has a camera then your implementation is pretty much moot. Perhaps you already know that and security is tight enough that cameras aren't allowed, but just figured I'd mention it.