diff --git a/src/Dockerfile b/src/Dockerfile
index e761f77..af8b4a4 100644
--- a/src/Dockerfile
+++ b/src/Dockerfile
@@ -9,5 +9,6 @@ ENV XDG_CACHE_HOME=/cache
 
 VOLUME ["/usr/local/share/ca-certificates"]
 
-ENTRYPOINT []
+ENTRYPOINT ["./update-ca.sh"]
+
 CMD ["./entrypoint.sh"]
diff --git a/src/update-ca.sh b/src/update-ca.sh
new file mode 100755
index 0000000..813f5f6
--- /dev/null
+++ b/src/update-ca.sh
@@ -0,0 +1,4 @@
+#!/bin/sh
+
+# Update CA certificates
+update-ca-certificates