diff --git a/.github/workflows/msh3.yml b/.github/workflows/msh3.yml
index 1379711..2dfa6aa 100644
--- a/.github/workflows/msh3.yml
+++ b/.github/workflows/msh3.yml
@@ -11,7 +11,7 @@ jobs:
   msh3:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - uses: docker/login-action@v3
         with:
@@ -37,7 +37,7 @@ jobs:
     needs: [msh3]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - name: build and test
         run: |
diff --git a/.github/workflows/ngtcp2.yml b/.github/workflows/ngtcp2.yml
index 04f8814..7455087 100644
--- a/.github/workflows/ngtcp2.yml
+++ b/.github/workflows/ngtcp2.yml
@@ -13,7 +13,7 @@ jobs:
     steps:
       - run: date +%Y-%m-%d
         id: date
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - uses: docker/login-action@v3
         with:
@@ -39,7 +39,7 @@ jobs:
     needs: [ngtcp2]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - name: build and test
         run: |
diff --git a/.github/workflows/quiche.yml b/.github/workflows/quiche.yml
index 101ea37..8985bda 100644
--- a/.github/workflows/quiche.yml
+++ b/.github/workflows/quiche.yml
@@ -11,7 +11,7 @@ jobs:
   quiche:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - uses: docker/login-action@v3
         with:
@@ -37,7 +37,7 @@ jobs:
     needs: [quiche]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: docker/setup-buildx-action@v3
       - name: build and test
         run: |