diff --git a/.github/workflows/mkdocs.yml b/.github/workflows/mkdocs.yml
index cbb9121b..cbeaf365 100644
--- a/.github/workflows/mkdocs.yml
+++ b/.github/workflows/mkdocs.yml
@@ -14,11 +14,11 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # pin@v4
+      - uses: actions/setup-python@39cd14951b08e74b54015e9e001cdefcf80e669f # pin@v5
         with:
           python-version: '3.11'
-      - uses: actions/cache@v4
+      - uses: actions/cache@0c45773b623bea8c8e75f6c82b208c3cf94ea4f9 # pin@v4
         with:
           key: ${{ github.ref }}
           path: .cache