diff --git a/opensearch-snapshots-alerting/Dockerfile b/opensearch-snapshots-alerting/Dockerfile
index 58c9462..ab2f37b 100644
--- a/opensearch-snapshots-alerting/Dockerfile
+++ b/opensearch-snapshots-alerting/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.11-slim-buster
+FROM python:3.11-slim-buster@sha256:c46b0ae5728c2247b99903098ade3176a58e274d9c7d2efeaaab3e0621a53935
 
 RUN apt update