diff --git a/.github/workflows/master.yml b/.github/workflows/master.yml
index 61b3dfe..373e1f4 100644
--- a/.github/workflows/master.yml
+++ b/.github/workflows/master.yml
@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: fetch source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v2.3.4
 
       - name: install node
         uses: actions/setup-node@v2