diff --git a/build/Dockerfile b/build/Dockerfile
index 65dbe93..94807d2 100644
--- a/build/Dockerfile
+++ b/build/Dockerfile
@@ -9,7 +9,7 @@ WORKDIR /build/
 COPY build.sh VERSION /build/
 RUN bash build.sh
 
-FROM ubuntu:focal
+FROM ubuntu:jammy
 LABEL maintainer="Xiaonan Shen <s@sxn.dev>"
 
 EXPOSE 25/tcp