diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 6206d42..495e47f 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -70,7 +70,7 @@ jobs:
           fetch-depth: 2
 
       - name: "Install PHP"
-        uses: shivammathur/setup-php@v2
+        uses: shivammathur/setup-php@f3e473d116dcccaddc5834248c87452386958240 # v2
         with:
           php-version: ${{ matrix.php-version }}
           ini-file: "development"