diff --git a/Dockerfile b/Dockerfile
index 97b987a..990b912 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # Build the manager binary
-FROM golang:1.21 as builder
+FROM golang:1.21@sha256:4746d26432a9117a5f58e95cb9f954ddf0de128e9d5816886514199316e4a2fb as builder
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
@@ -19,7 +19,7 @@ RUN CGO_ENABLED=0 GOOS=linux go build -a -o manager main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details
-FROM registry.access.redhat.com/ubi9/ubi-minimal
+FROM registry.access.redhat.com/ubi9/ubi-minimal@sha256:161a4e29ea482bab6048c2b36031b4f302ae81e4ff18b83e61785f40dc576f5d
 WORKDIR /
 COPY --from=builder /workspace/manager .
 USER 65532:65532
diff --git a/ci.Dockerfile b/ci.Dockerfile
index 724b6a1..1a39adb 100644
--- a/ci.Dockerfile
+++ b/ci.Dockerfile
@@ -1,4 +1,4 @@
-FROM registry.access.redhat.com/ubi9/ubi-minimal
+FROM registry.access.redhat.com/ubi9/ubi-minimal@sha256:161a4e29ea482bab6048c2b36031b4f302ae81e4ff18b83e61785f40dc576f5d
 WORKDIR /
 COPY bin/manager .
 USER 65532:65532
diff --git a/config/manager/kustomization.yaml b/config/manager/kustomization.yaml
index 79f0167..99f6c46 100644
--- a/config/manager/kustomization.yaml
+++ b/config/manager/kustomization.yaml
@@ -13,4 +13,4 @@ kind: Kustomization
 images:
 - name: controller
   newName: quay.io/raffaelespazzoli/patch-operator
-  newTag: latest
+  newTag: latest@sha256:47bf8e40af3def8af55b96ea5b85adfd4ada33d93f8d661cad233f4948c8b58f