diff --git a/.github/workflows/stale-issues.yml b/.github/workflows/stale-issues.yml
index 5fd78c25..312cab04 100644
--- a/.github/workflows/stale-issues.yml
+++ b/.github/workflows/stale-issues.yml
@@ -32,7 +32,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Mark/Close Stale Issues and Pull Requests
-        uses: actions/stale@v9
+        uses: actions/stale@28ca1036281a5e5922ead5184a1bbf96e5fc984e # v9
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           days-before-stale: 21
@@ -57,7 +57,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Mark/Close Stale `bump-formula-pr` and `bump-cask-pr` Pull Requests
-        uses: actions/stale@v9
+        uses: actions/stale@28ca1036281a5e5922ead5184a1bbf96e5fc984e # v9
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           days-before-stale: 2
diff --git a/.github/workflows/sync-shared-config.yml b/.github/workflows/sync-shared-config.yml
index 5c202f11..894c4891 100644
--- a/.github/workflows/sync-shared-config.yml
+++ b/.github/workflows/sync-shared-config.yml
@@ -57,7 +57,7 @@ jobs:
         uses: Homebrew/actions/setup-homebrew@master
 
       - name: Clone source repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
         with:
           persist-credentials: false
 
@@ -72,7 +72,7 @@ jobs:
           HOMEBREW_DEVELOPER: 1
 
       - name: Clone target repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
         with:
           repository: ${{ matrix.repo }}
           path: target/${{ matrix.repo }}
@@ -93,7 +93,7 @@ jobs:
         run: cp /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/.ruby-version .
 
       - name: Install Ruby
-        uses: ruby/setup-ruby@v1
+        uses: ruby/setup-ruby@161cd54b698f1fb3ea539faab2e036d409550e3c # v1.187.0
         with:
           bundler-cache: true