Can I kill pboxd?

The "com.apple.security.pboxd" process is taking 10-20% CPU, and has been for a while now.

From searching around, it seems that this is responsible for showing the "open file" dialog boxes on behalf of sandboxed apps.

It seems odd that it needs 40+ MB of RAM and 20% of my CPU to do this, especially since there don't seem to be any such dialog boxes visible right now.

Is it safe to kill this process?

Probably not a good idea. It has a very important job, displaying open and close dialog boxes in sandboxed apps (Most app store apps and some built-ins). Sandboxed apps cannot acess the filesystem directly and rely on this daemond to do it for them. Even if it relaunches, force killing parts of the OS can lead to instability and is generally a bad idea.

Source: http://arstechnica.com/apple/2011/07/mac-os-x-10-7/9/ (search page for "pboxd")

If it lets you kill it without being root, odds are that yes.

The "safe" alternative would be to restart, I guess...