diff --git a/.github/workflows/update-trivy-db.yaml b/.github/workflows/update-trivy-db.yaml
index fe52c38201..8bce97ebd7 100644
--- a/.github/workflows/update-trivy-db.yaml
+++ b/.github/workflows/update-trivy-db.yaml
@@ -7,6 +7,12 @@ on:
     - cron: '0 0 * * *'  # Run daily at midnight UTC
   workflow_dispatch:  # Allow manual triggering
 
+# Pulls the Trivy DB from GHCR (anonymous) and saves it to the GHA cache;
+# no source checkout is needed, only actions: write for the cache save.
+permissions:
+  contents: read
+  actions: write
+
 jobs:
   update-trivy-db:
     runs-on: ubuntu-latest