Reported based on MC-222405.
Players in Adventure mode or Visitor mode can interact with cauldrons, including:
Using buckets to add/remove liquids
Using bottles to add/remove water
Dying water
Dying leather armour using the water
This is probably only one issue, but if these turn out to be multiple issues, this ticket can be assumed to be tracking only the first point, namely, using buckets to add/remove liquids.
affects 1.17.30.20