diff --git a/.github/workflows/depup.yml b/.github/workflows/depup.yml
index 6f30d8a..6f37b79 100644
--- a/.github/workflows/depup.yml
+++ b/.github/workflows/depup.yml
@@ -11,7 +11,7 @@ jobs:
   reviewdog:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./with-pr
         with:
           file: testdata/testfile
@@ -22,7 +22,7 @@ jobs:
   redpen:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./with-pr
         with:
           file: testdata/testfile
@@ -34,7 +34,7 @@ jobs:
   themis:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./with-pr
         id: depup
         with:
diff --git a/.github/workflows/dockerimage.yml b/.github/workflows/dockerimage.yml
index 3f94a80..0402ca9 100644
--- a/.github/workflows/dockerimage.yml
+++ b/.github/workflows/dockerimage.yml
@@ -8,6 +8,6 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Build the Docker image
       run: docker build . --file Dockerfile --tag ${{ github.repository }}:$(date +%s)
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 9dd2136..55dc437 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -14,7 +14,7 @@ jobs:
     if: github.event.action != 'labeled'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # Bump version on merging Pull Requests with specific labels.
       # (bump:major,bump:minor,bump:patch)
@@ -50,6 +50,6 @@ jobs:
     if: github.event.action == 'labeled'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Post bumpr status comment
         uses: haya14busa/action-bumpr@v1
diff --git a/.github/workflows/reviewdog.yml b/.github/workflows/reviewdog.yml
index 74e033e..5ac0599 100644
--- a/.github/workflows/reviewdog.yml
+++ b/.github/workflows/reviewdog.yml
@@ -9,7 +9,7 @@ jobs:
     name: runner / shellcheck
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: haya14busa/action-cond@v1
         id: reporter
         with:
@@ -26,7 +26,7 @@ jobs:
     name: runner / hadolint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: haya14busa/action-cond@v1
         id: reporter
         with:
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 8496d06..b17bb9f 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -9,7 +9,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./
         id: depup
         with:
@@ -23,7 +23,7 @@ jobs:
   needless_prefix:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./
         id: depup
         with:
@@ -37,7 +37,7 @@ jobs:
   not_semver:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./
         id: depup
         with:
@@ -51,7 +51,7 @@ jobs:
   quoted_version:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./
         id: depup
         with:
@@ -65,7 +65,7 @@ jobs:
   tagged_version:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: ./
         id: depup
         with: