diff --git a/.github/test/oauth2/Dockerfile b/.github/test/oauth2/Dockerfile
index 5cf6f71c..632a9d94 100644
--- a/.github/test/oauth2/Dockerfile
+++ b/.github/test/oauth2/Dockerfile
@@ -1,8 +1,8 @@
-FROM registry.access.redhat.com/ubi9 AS ubi-micro-build
+FROM registry.access.redhat.com/ubi9@sha256:53d6c19d664f4f418ce5c823d3a33dbb562a2550ea249cf07ef10aa063ace38f AS ubi-micro-build
 RUN mkdir -p /mnt/rootfs
 RUN dnf install --installroot /mnt/rootfs curl jq --releasever 9 --setopt install_weak_deps=false --nodocs -y && \
     dnf --installroot /mnt/rootfs clean all && \
     rpm --root /mnt/rootfs -e --nodeps setup
 
-FROM quay.io/keycloak/keycloak:26.0.7
+FROM quay.io/keycloak/keycloak:26.0.7@sha256:4388e2379b7e870a447adbe7b80bd61f5fbf04e925832b19669fda4957f05a81
 COPY --from=ubi-micro-build /mnt/rootfs /