diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index d4c5abf62..e99c752f6 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -1958,6 +1958,8 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
                 if (rc != NGX_OK) {
                     return rc;
                 }
+            } else {
+              h->next = NULL;
             }
 
             ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,