diff --git a/.github/workflows/_build.yaml b/.github/workflows/_build.yaml
index c8bb409..f41bc0c 100644
--- a/.github/workflows/_build.yaml
+++ b/.github/workflows/_build.yaml
@@ -26,6 +26,18 @@ jobs:
   Build:
     runs-on: ${{ inputs.os }}
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: block
+          allowed-endpoints: >
+            api.github.com
+            files.pythonhosted.org:443
+            github.com:443
+            pypi.org:443
+            release-assets.githubusercontent.com:443
+
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
@@ -72,7 +84,7 @@ jobs:
         run: python -m build
 
       - name: Store the distribution packages
-        uses: actions/upload-artifact@v7.0.1
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         # upload artifacts with the oldest supported version
         if: runner.os == 'linux' && inputs.python-version == '3.9'
         with:
diff --git a/.github/workflows/_build_doc.yaml b/.github/workflows/_build_doc.yaml
index dc4dbe2..39f0865 100644
--- a/.github/workflows/_build_doc.yaml
+++ b/.github/workflows/_build_doc.yaml
@@ -25,6 +25,13 @@ jobs:
   Build:
     runs-on: ${{ inputs.os }}
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          egress-policy: audit
+          # sudo is required by the "Install dependencies" step below (apt-get pandoc)
+          disable-sudo: false
+
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
diff --git a/.github/workflows/_codeql.yaml b/.github/workflows/_codeql.yaml
index 1ec1dcc..6168e30 100644
--- a/.github/workflows/_codeql.yaml
+++ b/.github/workflows/_codeql.yaml
@@ -38,12 +38,18 @@ jobs:
     # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
 
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: audit
+
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@v4.36.2
+        uses: github/codeql-action/init@1a818fd5f97ed0ee9a823421bd5b171add01227f # v4.36.2
         with:
           languages: python
           # If you wish to specify custom queries, you can do so here or in a config file.
@@ -56,7 +62,7 @@ jobs:
       # Autobuild attempts to build any compiled languages  (C/C++, C#, Go, or Java).
       # If this step fails, then you should remove it and run the build manually (see below)
       - name: Autobuild
-        uses: github/codeql-action/autobuild@v4.36.2
+        uses: github/codeql-action/autobuild@1a818fd5f97ed0ee9a823421bd5b171add01227f # v4.36.2
 
       # ℹ️ Command-line programs to run using the OS shell.
       # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -69,6 +75,6 @@ jobs:
       #   ./location_of_script_within_repo/buildscript.sh
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v4.36.2
+        uses: github/codeql-action/analyze@1a818fd5f97ed0ee9a823421bd5b171add01227f # v4.36.2
         with:
           category: "/language:python"
diff --git a/.github/workflows/_pre_commit.yaml b/.github/workflows/_pre_commit.yaml
index 2208574..9102684 100644
--- a/.github/workflows/_pre_commit.yaml
+++ b/.github/workflows/_pre_commit.yaml
@@ -18,6 +18,12 @@ jobs:
   Pre-Commit:
     runs-on: ubuntu-latest
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: audit
+
       - name: Checkout
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
       - uses: pre-commit/action@2c7b3805fd2a0fd8c1884dcaebf91fc102a13ecd # v3.0.1
diff --git a/.github/workflows/_test.yaml b/.github/workflows/_test.yaml
index b301f49..9f9fd62 100644
--- a/.github/workflows/_test.yaml
+++ b/.github/workflows/_test.yaml
@@ -33,6 +33,12 @@ jobs:
       OS: ${{ inputs.os }}
       PYTHON: ${{ inputs.python-version }}
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: audit
+
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
diff --git a/.github/workflows/cicd.yaml b/.github/workflows/cicd.yaml
index ffd7e4d..f964568 100644
--- a/.github/workflows/cicd.yaml
+++ b/.github/workflows/cicd.yaml
@@ -103,14 +103,30 @@ jobs:
       name: testpypi
       url: https://test.pypi.org/p/python-cmethods
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: block
+          allowed-endpoints: >
+            api.github.com:443
+            fulcio.sigstore.dev
+            ghcr.io
+            github.com:443
+            pkg-containers.githubusercontent.com:443
+            rekor.sigstore.dev
+            test.pypi.org
+            tuf-repo-cdn.sigstore.dev
+            uploads.github.com:443
+
       - name: Download all the distributions
-        uses: actions/download-artifact@v8
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
           name: python-package-distributions
           path: dist/
 
       - name: Publish package distributions to Test PyPI
-        uses: pypa/gh-action-pypi-publish@release/v1
+        uses: pypa/gh-action-pypi-publish@cef221092ed1bacb1cc03d23a2d87d1d172e277b # release/v1
         with:
           repository-url: https://test.pypi.org/legacy/
 
@@ -138,13 +154,30 @@ jobs:
       name: pypi
       url: https://pypi.org/p/python-cmethods
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: block
+          allowed-endpoints: >
+            api.github.com:443
+            fulcio.sigstore.dev
+            ghcr.io
+            github.com:443
+            pkg-containers.githubusercontent.com:443
+            pypi.org
+            rekor.sigstore.dev
+            tuf-repo-cdn.sigstore.dev
+            upload.pypi.org
+            uploads.github.com:443
+
       - name: Download all the distributions
-        uses: actions/download-artifact@v8
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
           name: python-package-distributions
           path: dist/
 
       - name: Publish package distributions to PyPI
-        uses: pypa/gh-action-pypi-publish@release/v1
+        uses: pypa/gh-action-pypi-publish@cef221092ed1bacb1cc03d23a2d87d1d172e277b # release/v1
         with:
           repository-url: https://upload.pypi.org/legacy/
diff --git a/.github/workflows/dependabot_auto_approve.yaml b/.github/workflows/dependabot_auto_approve.yaml
index 50d8862..cd2886f 100644
--- a/.github/workflows/dependabot_auto_approve.yaml
+++ b/.github/workflows/dependabot_auto_approve.yaml
@@ -22,9 +22,15 @@ jobs:
     runs-on: ubuntu-latest
     if: ${{ github.actor == 'dependabot[bot]' }}
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: audit
+
       - name: Dependabot metadata
         id: dependabot-metadata
-        uses: dependabot/fetch-metadata@v3.1.0
+        uses: dependabot/fetch-metadata@25dd0e34f4fe68f24cc83900b1fe3fe149efef98 # v3.1.0
         with:
           github-token: "${{ secrets.GITHUB_TOKEN }}"
       - name: Approve a PR
diff --git a/.github/workflows/scorecard.yml b/.github/workflows/scorecard.yml
index 9f9b7e4..bbc9f11 100644
--- a/.github/workflows/scorecard.yml
+++ b/.github/workflows/scorecard.yml
@@ -31,6 +31,12 @@ jobs:
       # actions: read
 
     steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
+        with:
+          disable-sudo: true
+          egress-policy: audit
+
       - name: "Checkout code"
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with: