diff --git a/.github/workflows/schedule-update-actions.yml b/.github/workflows/schedule-update-actions.yml
index 4773301..bec498b 100644
--- a/.github/workflows/schedule-update-actions.yml
+++ b/.github/workflows/schedule-update-actions.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3.5.2
+      - uses: actions/checkout@v4.0.0
         with:
           # [Required] Access token with `workflow` scope.
           token: ${{ secrets.PAT }}
diff --git a/.github/workflows/template-sync.yml b/.github/workflows/template-sync.yml
index 49666bc..2556746 100644
--- a/.github/workflows/template-sync.yml
+++ b/.github/workflows/template-sync.yml
@@ -5,7 +5,7 @@ jobs:
   sync:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3.5.2 # important!
+      - uses: actions/checkout@v4.0.0 # important!
       - uses: euphoricsystems/action-sync-template-repository@v2.5.1
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/test_docker.yml b/.github/workflows/test_docker.yml
index 9555473..1cac1ba 100644
--- a/.github/workflows/test_docker.yml
+++ b/.github/workflows/test_docker.yml
@@ -11,7 +11,7 @@ jobs:
         python-version: ["3.10","3.11","3.12"]
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v4.0.0
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with: