diff --git a/charts/.utils/gitlab-ci.yaml b/charts/.utils/gitlab-ci.yaml
index 843ab75a6b780fd69def2e16625728f7a4e4d85f..6b27e2e6be3864e16b6067ead92edd3a81e19c51 100644
--- a/charts/.utils/gitlab-ci.yaml
+++ b/charts/.utils/gitlab-ci.yaml
@@ -14,7 +14,7 @@
 chart-package:
   stage: build
   extends: .chart-matrix
-  image: quay.io/shivering-isles/koolbox:2025.04
+  image: quay.io/shivering-isles/koolbox:2025.05
   script:
     - export TMP_DIR=$(mktemp -d)
     - helm package charts/${CHART} -d "$TMP_DIR"
@@ -28,7 +28,7 @@ chart-package:
 chart-helm-lint:
   stage: lint
   extends: .chart-matrix
-  image: quay.io/shivering-isles/koolbox:2025.04
+  image: quay.io/shivering-isles/koolbox:2025.05
   script:
     - helm lint --strict charts/${CHART}
   rules: