diff --git a/.github/workflows/build-images.yml b/.github/workflows/build-images.yml
index 2aa9e1d..fbc4584 100644
--- a/.github/workflows/build-images.yml
+++ b/.github/workflows/build-images.yml
@@ -10,7 +10,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
 
     - name: Log in to Docker Hub
       if: github.ref == 'refs/heads/master'