diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6541f009c..cc4e3dc66 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,6 +2,9 @@ name: CI
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   lint:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/indexing_top_gems.yml b/.github/workflows/indexing_top_gems.yml
index 8c04d864c..853a142ee 100644
--- a/.github/workflows/indexing_top_gems.yml
+++ b/.github/workflows/indexing_top_gems.yml
@@ -2,6 +2,9 @@ name: Index top 100 gems
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   indexing_top_gems:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/memleak.yml b/.github/workflows/memleak.yml
index 32009da61..6b479d94c 100644
--- a/.github/workflows/memleak.yml
+++ b/.github/workflows/memleak.yml
@@ -12,6 +12,9 @@ on:
       - "rust/**"
       - "ext/**"
 
+permissions:
+  contents: read
+
 jobs:
   memleak:
     runs-on: ubuntu-latest