diff --git a/.github/workflows/flake8.yml b/.github/workflows/flake8.yml
index 9acd55c..c964166 100644
--- a/.github/workflows/flake8.yml
+++ b/.github/workflows/flake8.yml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
 
       - name: Set up Python
         uses: actions/setup-python@v4