"Stained" is an unreleased track from 1999's The Fragile. Nothing about the track is known, nor if it is an alternative name for a track put onto the album at a later date. It is possible that the track is a working title for the track "Underneath It All", as the word "stained" features prominently in the song.
No track of this name was on the 2017 release The Fragile: Deviations 1, which was a compilation of instrumentals and extended or unused tracks from The Fragile sessions.
It is one of two tracks that feature in background photos from this era that remain unreleased, the other being "Rotation".