diff --git a/.github/workflows/documentation.yml b/.github/workflows/documentation.yml
index b8bf7972b0f766..4baa428e93b439 100644
--- a/.github/workflows/documentation.yml
+++ b/.github/workflows/documentation.yml
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-18.04
     steps:
     - name: Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2.3.4
       with:
         fetch-depth: 50
     - name: Run website_build.sh
diff --git a/.github/workflows/epochs.yml b/.github/workflows/epochs.yml
index a605a818c5f390..a499deba672659 100644
--- a/.github/workflows/epochs.yml
+++ b/.github/workflows/epochs.yml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-18.04
     steps:
     - name: Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2.3.4
     - name: Run epochs_update.sh
       # Use a conditional step instead of a conditional job to work around #20700.
       if: github.repository == 'web-platform-tests/wpt'
diff --git a/.github/workflows/manifest.yml b/.github/workflows/manifest.yml
index 3210c703b1d8f8..dd6d6c3c2674a1 100644
--- a/.github/workflows/manifest.yml
+++ b/.github/workflows/manifest.yml
@@ -15,7 +15,7 @@ jobs:
       with:
         python-version: '3.x'
     - name: Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2.3.4
       with:
         fetch-depth: 50
     - name: Install dependencies
diff --git a/.github/workflows/pull_request_previews.yml b/.github/workflows/pull_request_previews.yml
index 676aff3021242b..2e5fcca392f804 100644
--- a/.github/workflows/pull_request_previews.yml
+++ b/.github/workflows/pull_request_previews.yml
@@ -17,7 +17,7 @@ jobs:
   update-pr-preview:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2.3.4
       with:
         fetch-depth: 1
     - name: Install dependency
diff --git a/.github/workflows/regen_certs.yml b/.github/workflows/regen_certs.yml
index 33699d833aad7c..9c86f6d5b346fc 100644
--- a/.github/workflows/regen_certs.yml
+++ b/.github/workflows/regen_certs.yml
@@ -13,7 +13,7 @@ jobs:
       with:
         python-version: '3.x'
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v2.3.4
     - name: Regenerate certs
       # Use a conditional step instead of a conditional job to work around #20700.
       if: github.repository == 'web-platform-tests/wpt'