diff --git a/Dockerfile b/Dockerfile
index c9853e3..e97e9df 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.7-buster
+FROM python:3.7-buster@sha256:65f08bc4dfb68700010a2ea85fd385de826f624ede6349b05a65aa857456f987
 EXPOSE 8501
 WORKDIR /code
 COPY requirements.txt requirements.txt