diff --git a/.github/workflows/ios.yml b/.github/workflows/ios.yml
index 6b40235..f9e909d 100644
--- a/.github/workflows/ios.yml
+++ b/.github/workflows/ios.yml
@@ -10,7 +10,7 @@ jobs:
     runs-on: macOS-latest
     timeout-minutes: 30
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
       with:
         submodules: true
     - uses: Apple-Actions/import-codesign-certs@v1