diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 1ed0a799..4a0f0046 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -1,4 +1,8 @@
 name: Build Docker images
+
+permissions:
+  contents: read
+
 on: [pull_request]
 
 env: