diff --git a/.github/workflows/linter.yml b/.github/workflows/linter.yml
index e065b75..784cf99 100644
--- a/.github/workflows/linter.yml
+++ b/.github/workflows/linter.yml
@@ -6,7 +6,7 @@ jobs:
   linter:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v2.3.4
       - name: Use Node.js 14.x
         uses: actions/setup-node@v2.1.5
         with:
diff --git a/.github/workflows/snyk.yml b/.github/workflows/snyk.yml
index 5b8ee8a..8e0d8ed 100644
--- a/.github/workflows/snyk.yml
+++ b/.github/workflows/snyk.yml
@@ -9,7 +9,7 @@ jobs:
   security:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v2.3.4
       - name: Use Node.js 14.x
         uses: actions/setup-node@v2.1.5
         with:
diff --git a/.github/workflows/tester.yml b/.github/workflows/tester.yml
index de7807d..0d9d26f 100644
--- a/.github/workflows/tester.yml
+++ b/.github/workflows/tester.yml
@@ -11,7 +11,7 @@ jobs:
         node-version: ['12', '14', '15', '16']
       fail-fast: false
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v2.3.4
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v2.1.5
         with:
@@ -35,7 +35,7 @@ jobs:
         os: [ubuntu-latest]
         node-version: ['14.x']
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v2.3.4
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v2.1.5
         with: