diff --git a/.github/workflows/pages.yml b/.github/workflows/pages.yml
index 744b24c..015aba3 100644
--- a/.github/workflows/pages.yml
+++ b/.github/workflows/pages.yml
@@ -24,11 +24,11 @@ jobs:
       url: ${{ steps.deployment.outputs.page_url }}
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/configure-pages@v5
-      - uses: actions/upload-pages-artifact@v3
+      - uses: actions/checkout@fbc6f3992d24b796d5a048ff273f7fcc4a7b6c09 # v5
+      - uses: actions/configure-pages@983d7736d9b0ae728b81ab479565c72886d7745b # v5
+      - uses: actions/upload-pages-artifact@56afc609e74202658d3ffba0e8f6dda462b719fa # v3
         with:
           path: site
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@d6db90164ac5ed86f2b6aed7e0febac5b3c0c03e # v4
diff --git a/.github/workflows/validate-publication.yml b/.github/workflows/validate-publication.yml
index c32af9d..7b4d7dd 100644
--- a/.github/workflows/validate-publication.yml
+++ b/.github/workflows/validate-publication.yml
@@ -12,7 +12,7 @@ jobs:
   public-artifacts:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@fbc6f3992d24b796d5a048ff273f7fcc4a7b6c09 # v5
 
       - name: Validate dataset and result JSON
         shell: bash
@@ -27,8 +27,8 @@ jobs:
         shell: bash
         run: |
           set -euo pipefail
-          ! grep -RIl '/Users/' dataset results site
-          ! grep -RIl 'repoqa' dataset results site
+          if grep -RIl '/Users/' dataset results site >/dev/null; then exit 1; fi
+          if grep -RIl 'repoqa' dataset results site >/dev/null; then exit 1; fi
           test -z "$(find . -type f -size +50M -not -path './.git/*' -print -quit)"
 
   frontend:
@@ -37,8 +37,8 @@ jobs:
       run:
         working-directory: src/RepoContextBench/ReportFrontend
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
+      - uses: actions/checkout@fbc6f3992d24b796d5a048ff273f7fcc4a7b6c09 # v5
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
         with:
           node-version: 22
           cache: npm