diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ec1ef041b2068..6693182e0c578 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -25,11 +25,15 @@ name: CI
   pull_request:
     branches:
       - "**"
+permissions:
+  contents: read
 defaults:
   run:
     shell: bash
 jobs:
   pr:
+    permissions:
+      actions: write
     name: PR
     env:
       CI_JOB_NAME: "${{ matrix.name }}"
@@ -142,6 +146,8 @@ jobs:
           AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.ARTIFACTS_AWS_ACCESS_KEY_ID)] }}"
         if: "success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
   auto:
+    permissions:
+      actions: write
     name: auto
     env:
       CI_JOB_NAME: "${{ matrix.name }}"
@@ -547,6 +553,8 @@ jobs:
           AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.ARTIFACTS_AWS_ACCESS_KEY_ID)] }}"
         if: "success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
   try:
+    permissions:
+      actions: write
     name: try
     env:
       CI_JOB_NAME: "${{ matrix.name }}"
diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index 7826fd514093e..f020c31079e5e 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -264,6 +264,9 @@ on:
     branches:
       - "**"
 
+permissions:
+  contents: read
+
 defaults:
   run:
     # On Linux, macOS, and Windows, use the system-provided bash as the default
@@ -273,6 +276,8 @@ defaults:
 
 jobs:
   pr:
+    permissions:
+      actions: write # for rust-lang/simpleinfra/github-actions/cancel-outdated-builds
     <<: *base-ci-job
     name: PR
     env:
@@ -293,6 +298,8 @@ jobs:
             <<: *job-linux-xl
 
   auto:
+    permissions:
+      actions: write # for rust-lang/simpleinfra/github-actions/cancel-outdated-builds
     <<: *base-ci-job
     name: auto
     env:
@@ -719,6 +726,8 @@ jobs:
             <<: *job-windows-xl
 
   try:
+    permissions:
+      actions: write # for rust-lang/simpleinfra/github-actions/cancel-outdated-builds
     <<: *base-ci-job
     name: try
     env: