diff --git a/1.2.1/nginx-mainline/alpine/Dockerfile b/1.2.1/nginx-mainline/alpine/Dockerfile
index 783fe07..c8471b8 100644
--- a/1.2.1/nginx-mainline/alpine/Dockerfile
+++ b/1.2.1/nginx-mainline/alpine/Dockerfile
@@ -1,4 +1,4 @@
-FROM nginx:1.15.10-alpine
+FROM nginx:1.21.1-alpine
 
 ENV NGINX_RTMP_MODULE_VERSION 1.2.1