diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e82f172..cc47389 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,6 +6,9 @@ on:
   pull_request:
     branches: [ master ]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Build & Test (JDK ${{ matrix.java-version }})