Code Ape Tech Column

Mar 24, 2022 · Backend Development

Resolving Duplicate Access-Control-Allow-Origin Header Issues in Spring Cloud Gateway

This article explains why Spring Cloud Gateway may return multiple Access-Control-Allow-Origin headers, analyzes the internal processing flow that causes the duplication, and provides two practical solutions—using DedupeResponseHeader configuration or a custom GlobalFilter—to ensure a single, correct CORS header in responses.