diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 84cea31..f2e5b57 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -14,7 +14,7 @@ jobs:
         python-version: ["3.10"]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
@@ -47,7 +47,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
@@ -77,7 +77,7 @@ jobs:
     if: ${{ github.ref=='refs/heads/main' && github.event_name!='pull_request' }}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
       - name: Setup Python
         uses: actions/setup-python@v4
         with: