diff --git a/action.yml b/action.yml
index f250922..74105a5 100644
--- a/action.yml
+++ b/action.yml
@@ -49,7 +49,7 @@ runs:
             ;;
         esac
     - name: Cache dune’s cache and build artefacts
-      uses: actions/cache@v5
+      uses: actions/cache@8b402f58fbc84540c8b491a91e594a4576fec3d7 # v5.0.2
       id: dune-cache
       with:
         path: |