It has been reported and they attempted to fix (Stated as "likely fixed"). However, I still see it auto fill out the PIN sometimes when I expand the advanced section of my dashboards sometimes. I just know to be aware that it can happen now and make sure to check it before I save (happened as recently as a couple weeks ago).
If I could replicate it on demand, I would add to the bug report. But, it seems to be random (maybe specific dashboards, or maybe just specific steps..... did not see a pattern though)