diff --git a/Dockerfile b/Dockerfile
index 9295b59..9f112cb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # hadolint ignore=DL3006
-FROM squidfunk/mkdocs-material
+FROM squidfunk/mkdocs-material:9.5.3
 
 # Beispiel; https://squidfunk.github.io/mkdocs-material/getting-started/
 # hadolint ignore=DL3013