diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c2036af..372e0b1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
     steps:
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
     - name: Set up Ruby
-      uses: ruby/setup-ruby@v1
+      uses: ruby/setup-ruby@0cb964fd540e0a24c900370abf38a33466142735 # v1.305.0
       with:
         ruby-version: ${{ matrix.ruby }}
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically