diff --git a/spamd/Dockerfile b/spamd/Dockerfile
index 5651e9ebf2ad1b7e744b31c1a7d0183bce930711..faf5789f96d364102b0b0287882d6180db55d2bf 100644
--- a/spamd/Dockerfile
+++ b/spamd/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:buster-slim
+FROM debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \