I am a new Slackware user. I have been enjoying a mostly stably-working system for about a month now. But today I heard about a newly discovered kernel vulnerability, so I issued slackpkg update, followed by slackpkg upgrade-all. There was a lot to be upgraded, especially considering that I executed this exact sequence a month ago. I was expecting not to have to do this for six months or so. I guess virtualbox got upgraded because now it doesn't work at all. It tells me this when I try to open it:

Now I am aware that I could simply downgrade and install the old version through sbopkg, but I'd like to know if there's an easy fix for this new version first.

It didn't work.

no not that part of the thread, the other part, rebuilding virtualbox, then on the other hand, don't bother with slackbuilds virtualbox, I would remove what you installed and follow this excellant post by tronayne, that's what I've been doing all these years

you'll want to dl the current versions of course