diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index d8a7aff..63ebba4 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -38,7 +38,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
     - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 6daaa76..10ca699 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-24.04
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
@@ -28,7 +28,7 @@ jobs:
     if: ${{ github.event_name == 'push' }}
     needs: build
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: mattnotmitt/doxygen-action@v1
       - name: Deploy
         uses: peaceiris/actions-gh-pages@v4
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index c3ac600..c3bf6d8 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -7,7 +7,7 @@ jobs:
   publish:
     runs-on: ubuntu-24.04
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with: