diff --git a/.github/workflows/microshed-ci.yml b/.github/workflows/microshed-ci.yml
index 0c29875e..21f20e71 100644
--- a/.github/workflows/microshed-ci.yml
+++ b/.github/workflows/microshed-ci.yml
@@ -28,7 +28,7 @@ jobs:
     name: Build ${{ matrix.java }}, ${{ matrix.os }}
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
     - name: Set up Java
       uses: actions/setup-java@v3
       with: