diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b5ce74c..b09dc8e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           fetch-depth: 0
       - name: Fix tags
@@ -23,7 +23,7 @@ jobs:
       - name: Move packages
         run: mv bin/Release/*.TapPackage .
       - name: Upload artifacts
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
         with:
           name: package
           retention-days: 5
@@ -37,12 +37,12 @@ jobs:
       - Build
     steps:
       - name: Download Artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
           name: package
           path: ./
       - name: Setup OpenTAP
-        uses: opentap/setup-opentap@v1.0
+        uses: opentap/setup-opentap@6eee68cf35f2e861f93d21029bbe7af4c427b9bd #main (pending v1.1)
         with:
           version: 9.18.4
       - name: Install PackagePublish
diff --git a/.github/workflows/pr-comment.yml b/.github/workflows/pr-comment.yml
index 58b8471..d843e2d 100644
--- a/.github/workflows/pr-comment.yml
+++ b/.github/workflows/pr-comment.yml
@@ -17,7 +17,7 @@ jobs:
     name: pr-version-comment
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           # This action needs the entire history of the repository to calculate the version
           fetch-depth: 0