diff --git a/.github/workflows/phpunit.yml b/.github/workflows/phpunit.yml
index b52367e..f00afe9 100644
--- a/.github/workflows/phpunit.yml
+++ b/.github/workflows/phpunit.yml
@@ -6,6 +6,9 @@ on:
     branches:
       - master
 
+permissions:
+  contents: read
+
 jobs:
   phpunit:
     name: "PHPUnit tests"