diff --git a/Dockerfile b/Dockerfile
index 3dea8b1..1579b78 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:bulleyes-slim
+FROM debian:bullseye-slim
 
 ARG SQUID_VERSION
 ENV ENV_SQUID_VERSION=$SQUID_VERSION