diff --git a/.drone.yml b/.drone.yml
index 42b0b8a..1d01f00 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -15,7 +15,7 @@ trigger:
 
 steps:
   - name: install-lint-test
-    image: python:3.8.18-alpine
+    image: python:3.8.18-alpine@sha256:0ef73cdd8a926f9152586a6b2c7c4ca9e9c43ca7a91cffb32957d836db200090
     env:
       PYROOT: '/pyroot'
       PYTHONUSERBASE: '/pyroot'
@@ -93,7 +93,7 @@ trigger:
 
 steps:
   - name: install-lint-test
-    image: python:3.8.18-alpine
+    image: python:3.8.18-alpine@sha256:0ef73cdd8a926f9152586a6b2c7c4ca9e9c43ca7a91cffb32957d836db200090
     env:
       PYROOT: '/pyroot'
       PYTHONUSERBASE: '/pyroot'
diff --git a/Dockerfile b/Dockerfile
index 304abf6..4c6d66a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
-FROM python:3.8.18-alpine AS builder
+FROM python:3.8.18-alpine@sha256:0ef73cdd8a926f9152586a6b2c7c4ca9e9c43ca7a91cffb32957d836db200090 AS builder
 
 ENV PYROOT=/pyroot
 ENV PYTHONUSERBASE=$PYROOT
@@ -20,7 +20,7 @@ RUN PIP_USER=1 PIP_IGNORE_INSTALLED=1 pipenv install --system --deploy --ignore-
 RUN pip3 uninstall --yes pipenv
 
 
-FROM python:3.8.18-alpine AS ki-backend
+FROM python:3.8.18-alpine@sha256:0ef73cdd8a926f9152586a6b2c7c4ca9e9c43ca7a91cffb32957d836db200090 AS ki-backend
 
 ENV PYROOT=/pyroot
 ENV PYTHONUSERBASE=$PYROOT