diff --git a/git/Dockerfile b/git/Dockerfile
index 87cb3d1ab..094a06eee 100644
--- a/git/Dockerfile
+++ b/git/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:24.04
+FROM ubuntu:24.04@sha256:278628f08d4979fb9af9ead44277dbc9c92c2465922310916ad0c46ec9999295
 
 RUN apt-get update && apt-get install --no-install-recommends -y git=1:2.43.0-1ubuntu7.1 openssh-client=1:9.6p1-3ubuntu13.4 && rm -rf /var/lib/apt/lists/*
 
diff --git a/github-backup/Dockerfile b/github-backup/Dockerfile
index 2180effdb..2cb02f808 100644
--- a/github-backup/Dockerfile
+++ b/github-backup/Dockerfile
@@ -1,4 +1,4 @@
-FROM bitnami/python:3.10
+FROM bitnami/python:3.10@sha256:856e5b9740c7e800daf66392817bf624b20ddd5cf84841dc87aba8e4f4a2f715
 
 # hadolint ignore=DL3008
 RUN apt-get update && apt-get install -y --no-install-recommends git openssh-client && rm -rf /var/lib/apt/lists/*