Sounds like a mold issue.
What About Pink Stains on Linoleum Floor?
You may have found our blog because you were concerned about the pink stains on your linoleum or vinyl floor. Why is your vinyl floor turning pink?
These same bacteria are most likely the cause of the problem, especially if moisture is being trapped under your floors.
Bacteria could be growing on your subfloor with the dye migrating upwards over time, causing the mysterious pink stains on your linoleum floor to magically appear
Orange to rust colored spots may appear and are attributed to mold and mildew that can also produce stain causing pigments