diff --git a/Dockerfile b/Dockerfile
index a13c703..9b8dd5e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -8,26 +8,28 @@ ARG RELEASETOOL_URL="https://home.hottis.de/gitlab/wolutator/gitlabreleaseupload
 
 
 RUN \
-  apt-get update && \
-  apt-get install -y make && \
-  apt-get install -y openssh-client && \
-  apt-get install -y git && \
-  apt-get install -y python && \
-  apt-get install -y python-requests && \
-  apt-get install -y python-pycodestyle && \
-  apt-get install -y python-yaml && \
-  apt-get install -y python-pip && \
-  apt-get install -y python-xmltodict && \
-  apt-get install -y gpg && \
-  apt-get install -y apt-transport-https && \
-  apt-get install -y wget && \
-  apt-get install -y curl && \
-  apt-get install -y unzip && \
-  apt-get install -y zip && \
-  apt-get install -y vim.tiny && \
-  apt-get install -y p7zip-full && \
-  apt-get install -y procps && \
-  apt-get install -y doxygen && \
+  apt update && \
+  apt upgrade -y && \
+  apt install -y ca-certificates && \
+  apt install -y make && \
+  apt install -y openssh-client && \
+  apt install -y git && \
+  apt install -y python && \
+  apt install -y python-requests && \
+  apt install -y python-pycodestyle && \
+  apt install -y python-yaml && \
+  apt install -y python-pip && \
+  apt install -y python-xmltodict && \
+  apt install -y gpg && \
+  apt install -y apt-transport-https && \
+  apt install -y wget && \
+  apt install -y curl && \
+  apt install -y unzip && \
+  apt install -y zip && \
+  apt install -y vim.tiny && \
+  apt install -y p7zip-full && \
+  apt install -y procps && \
+  apt install -y doxygen && \
   rm -rf /var/lib/apt/lists/* && \
   cd /tmp && \
   wget $RELEASETOOL_URL && \
@@ -38,3 +40,4 @@ RUN \
   mv gitlabreleaseuploader.py /usr/bin && \
   mv deleterelease.py /usr/bin && \
   mv checksemver.py /usr/bin
+