Brake fluid is corrosive? Water is corrosive. Getting water in brake fluid makes the mix corrosive. Brake fluid comes in a metal can that doesn't corrode until you put water in it.
Brake fluid will peel off paint and other protective coatings. That will leave those parts subject to corrosion. By all means rinse the spill immediately with lots of water. If paint has started to bubble, get the area treated to prevent corrosion.