diff --git a/clamd/Dockerfile b/clamd/Dockerfile
index 9a211456e31e4e18e81f774d17d0046aac53fab9..5e0e9bc04b1e45acc842c26a32689c5fa89bceaf 100644
--- a/clamd/Dockerfile
+++ b/clamd/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
diff --git a/dovecot/Dockerfile b/dovecot/Dockerfile
index eba63ce5205a49bd8f78dfca5202237415a7914d..550793b67d81eb992d310419399dbfa548f57f9a 100644
--- a/dovecot/Dockerfile
+++ b/dovecot/Dockerfile
@@ -1,11 +1,11 @@
-FROM buildpack-deps:bullseye as delete_to_trash
+FROM docker.io/buildpack-deps:bullseye as delete_to_trash
 # hadolint ignore=DL3008,DL3015
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive  apt-get install -y dovecot-dev && \
     git clone https://github.com/pali/dovecot_deleted_to_trash && \
     make -C dovecot_deleted_to_trash
 
-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
diff --git a/exim4/Dockerfile b/exim4/Dockerfile
index e6261c82c80199646e0a12ea1775902dc192643a..b84257c52b5438cd9388864681dde57b4c58427b 100644
--- a/exim4/Dockerfile
+++ b/exim4/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008,DL4006
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
diff --git a/spamd/Dockerfile b/spamd/Dockerfile
index faf5789f96d364102b0b0287882d6180db55d2bf..3acaaf24b4729bd60e8f595ee1a13ee395a8cea7 100644
--- a/spamd/Dockerfile
+++ b/spamd/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \