diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4a57feba..16b8cebc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,9 +5,9 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
       - name: Repository lampy
-        uses: actions/checkout@v3
+        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
         with:
           submodules: recursive
           ref: 'v2.0'
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 43827d68..f353d599 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v2