diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index cdb385f2..6eeb3925 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -25,9 +25,9 @@ jobs:
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v2
+      - uses: actions/setup-python@v4.3.0
         with:
-          python-version: 3.x
+          python-version: 3.9
 
       - name: Install Python dependencies
         run: pip install -r docs/requirements.txt
diff --git a/.github/workflows/post-release.yml b/.github/workflows/post-release.yml
index 706d31e4..fdb7d493 100644
--- a/.github/workflows/post-release.yml
+++ b/.github/workflows/post-release.yml
@@ -35,9 +35,9 @@ jobs:
             exit 1
           fi
 
-      - uses: actions/setup-python@v2
+      - uses: actions/setup-python@v4.3.0
         with:
-          python-version: 3.x
+          python-version: 3.9
 
       - name: Install Python dependencies
         run: pip install -r docs/requirements.txt
diff --git a/.github/workflows/test-docs.yml b/.github/workflows/test-docs.yml
index 9ea643ab..9fb4d288 100644
--- a/.github/workflows/test-docs.yml
+++ b/.github/workflows/test-docs.yml
@@ -33,9 +33,9 @@ jobs:
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v2
+      - uses: actions/setup-python@v4.3.0
         with:
-          python-version: 3.x
+          python-version: 3.9
 
       - name: Install Python dependencies
         run: pip install -r docs/requirements.txt