diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index bfdb3ad8d..10c3e9ddd 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -300,7 +300,7 @@ jobs:
       - frontend-build
     services:
       dex:
-        image: ghcr.io/go-vikunja/dex-testing:main
+        image: ghcr.io/go-vikunja/dex-testing:main@sha256:7440cd3a24658571c01d15604ac89923366e5fac748d5f8722cd6f9c0dfa47f8
         ports:
           - 5556:5556
     strategy:
diff --git a/frontend/cypress/docker-compose.yml b/frontend/cypress/docker-compose.yml
index aadbdb851..136577a39 100644
--- a/frontend/cypress/docker-compose.yml
+++ b/frontend/cypress/docker-compose.yml
@@ -1,6 +1,6 @@
 services:
   dex:
-    image: ghcr.io/go-vikunja/dex-testing:main
+    image: ghcr.io/go-vikunja/dex-testing:main@sha256:7440cd3a24658571c01d15604ac89923366e5fac748d5f8722cd6f9c0dfa47f8
     ports:
       - 5556:5556
   cypress: