diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6d1d38f..a305eef 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -34,7 +34,7 @@ jobs:
       # matrix の Ruby に切り替わる。system 行では何もしない (macOS 標準 Ruby のまま)。
       - name: Set up Ruby ${{ matrix.ruby }}
         if: matrix.ruby != 'system'
-        uses: ruby/setup-ruby@d45b1a4e94b71acab930e56e79c6aa188764e7f9 # v1.316.0
+        uses: ruby/setup-ruby@95ef2b042f9d7a56d8268cba8559e2842e2ad01b # v1.321.0
         with:
           ruby-version: ${{ matrix.ruby }}