Does rye whiskey ever go bad?

Yes, rye whiskey does eventually go bad. Although it has a long shelf life due to its high alcohol content, rye whiskey will slowly start to degrade overtime. This is because the alcohol and other compounds break down and oxidize when exposed to air, causing changes in both taste and color. While the rye whiskey might never become unsafe to drink, after about 10 years it will generally begin to develop an unpleasant musty taste and aroma similar to cardboard.