[sdwedq]

Seems like a good idea but a bit too complex, first you need to find an OS project that is close to your company's projects. It may work for PHP or JavaScript but not sure if it would work in less popular languages.

Then many bugs that appear simple might be a lot more involved. I have looked for easy bugs in my favorite open source projects, there are not many. All low hanging fruits get taken care of immediately in popular projects.

Then there are many semi-abandoned projects, so even if candidate fix the bug, it may not go anywhere.

And if you do find actively developed project, how long before maintainers accept the bug. Are you going to wait and see how candidate answers maintainer's questions and get their changes merged in?

Are you going to pay candidate for the work? Otherwise, if this becomes common, companies may take advantage of candidates to have them fix bugs in softwares they use.