diff --git a/packages/vite/src/node/http.ts b/packages/vite/src/node/http.ts
index 51a063ba800ccf..8a12179645fd23 100644
--- a/packages/vite/src/node/http.ts
+++ b/packages/vite/src/node/http.ts
@@ -75,7 +75,10 @@ export interface CommonServerOptions {
 export interface CorsOptions {
   origin?:
     | CorsOrigin
-    | ((origin: string, cb: (err: Error, origins: CorsOrigin) => void) => void)
+    | ((
+        origin: string | undefined,
+        cb: (err: Error, origins: CorsOrigin) => void,
+      ) => void)
   methods?: string | string[]
   allowedHeaders?: string | string[]
   exposedHeaders?: string | string[]