diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 04e41843..6d3c9317 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,8 +14,8 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
+      - uses: actions/setup-node@f1f314fca9dfce2769ece7d933488f076716723e # v1
         with:
           node-version: 12.x
       - run: npm ci
@@ -23,11 +23,11 @@ jobs:
       - run: npm run format-check
       - run: npm run lint
       - run: npm run test
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@82c141cc518b40d92cc801eee768e7aafc9c2fa2 # v2
         with:
           name: dist
           path: dist
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@82c141cc518b40d92cc801eee768e7aafc9c2fa2 # v2
         with:
           name: action.yml
           path: action.yml
@@ -40,14 +40,14 @@ jobs:
       matrix:
         target: [built, committed]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
       - if: matrix.target == 'built' || github.event_name == 'pull_request'
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@cbed621e49e4c01b044d60f6c80ea4ed6328b281 # v2
         with:
           name: dist
           path: dist
       - if: matrix.target == 'built' || github.event_name == 'pull_request'
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@cbed621e49e4c01b044d60f6c80ea4ed6328b281 # v2
         with:
           name: action.yml
           path: .
@@ -70,13 +70,13 @@ jobs:
     needs: [test]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/download-artifact@v2
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
+      - uses: actions/download-artifact@cbed621e49e4c01b044d60f6c80ea4ed6328b281 # v2
         with:
           name: dist
           path: dist
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@v3
+        uses: peter-evans/create-pull-request@18f7dc018cc2cd597073088f7c7591b9d1c02672 # v3
         with:
           commit-message: Update distribution
           title: Update distribution
diff --git a/.github/workflows/on-repository-dispatch.yml b/.github/workflows/on-repository-dispatch.yml
index 34fcd432..af2d43d4 100644
--- a/.github/workflows/on-repository-dispatch.yml
+++ b/.github/workflows/on-repository-dispatch.yml
@@ -11,7 +11,7 @@ jobs:
           PAYLOAD_CONTEXT: ${{ toJson(github.event.client_payload) }}
         run: echo "$PAYLOAD_CONTEXT"
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
         if: github.event.client_payload.ref != ''
         with:
           ref: ${{ github.event.client_payload.ref }}
diff --git a/.github/workflows/slash-command-dispatch.yml b/.github/workflows/slash-command-dispatch.yml
index d4ad85d1..7b616c67 100644
--- a/.github/workflows/slash-command-dispatch.yml
+++ b/.github/workflows/slash-command-dispatch.yml
@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Slash Command Dispatch
-        uses: peter-evans/slash-command-dispatch@v2
+        uses: peter-evans/slash-command-dispatch@40877f718dce0101edfc7aea2b3800cc192f9ed5 # v2
         with:
           token: ${{ secrets.ACTIONS_BOT_TOKEN }}
           config: >
diff --git a/.github/workflows/update-dep.yml b/.github/workflows/update-dep.yml
index e59a8058..6c64d604 100644
--- a/.github/workflows/update-dep.yml
+++ b/.github/workflows/update-dep.yml
@@ -6,8 +6,8 @@ jobs:
   update-dep:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
+      - uses: actions/setup-node@f1f314fca9dfce2769ece7d933488f076716723e # v1
         with:
           node-version: '12.x'
       - name: Update dependencies
@@ -15,7 +15,7 @@ jobs:
           npx -p npm-check-updates ncu -u
           npm install
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@v3
+        uses: peter-evans/create-pull-request@18f7dc018cc2cd597073088f7c7591b9d1c02672 # v3
         with:
             token: ${{ secrets.ACTIONS_BOT_TOKEN }}
             commit-message: Update dependencies