What does it mean when water is leaking inside of a refrigerator?

Water leaking inside a refrigerator usually means the defrost drain is blocked, according to SFGate. Condensation from the freezer is removed via the defrost drain, which empties into a pan under the unit. Cool temperatures can freeze the drain, or it can become clogged by foreign material.

Unstopping the drain pipe can be accomplished by running a plumbing snake through the pipe. The vegetable crisper drawers should be removed to access the pipe. After using the plumbing snake, flushing the pipe with a solution of warm water and baking soda can further loosen ice and debris. The baking soda solution drains back into the drain pan along with the debris causing the clog.