diff --git a/Jenkinsfile b/Jenkinsfile
index 1b615e38304c..50eee01fa974 100755
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -45,7 +45,7 @@
 // 'python3 jenkins/generate.py'
 // Note: This timestamp is here to ensure that updates to the Jenkinsfile are
 // always rebased on main before merging:
-// Generated at 2022-08-26T15:48:19.597592
+// Generated at 2022-08-30T11:58:06.036509
 
 import org.jenkinsci.plugins.pipeline.modeldefinition.Utils
 // NOTE: these lines are scanned by docker/dev_common.sh. Please update the regex as needed. -->
@@ -169,6 +169,7 @@ def init_git() {
     """,
     label: 'Update git submodules',
   )
+  checkout_trusted_files()
 }
 
 def docker_init(image) {
@@ -248,6 +249,30 @@ def cancel_previous_build() {
   }
 }
 
+def checkout_trusted_files() {
+  // trust everything from branch builds
+  if (!env.BRANCH_NAME.startsWith('PR-')) {
+    return;
+  }
+
+  // trust peoople listed in CONTRIBUTING.md
+  grep_code = sh(
+    returnStatus: true,
+    script: "git show '${upstream_revision}:CONTRIBUTORS.md' | grep '@${env.CHANGE_AUTHOR}'",
+    label: 'Check if change is from a contributor',
+  )
+
+  if (grep_code == 1) {
+    // Any scripts that run on the bare host and not inside a Docker container
+    // (especially those that access secrets) should be checked out here so
+    // only trusted versions are used in CI
+    sh(
+      script: "git checkout ${upstream_revision} ci/scripts/.",
+      label: 'Check out trusted files',
+    )
+  }
+}
+
 def should_skip_ci(pr_number) {
   if (env.BRANCH_NAME == null || !env.BRANCH_NAME.startsWith('PR-')) {
     // never skip CI on build sourced from a branch
diff --git a/ci/jenkins/Prepare.groovy.j2 b/ci/jenkins/Prepare.groovy.j2
index 404d2870c9e2..94575a7b4b64 100644
--- a/ci/jenkins/Prepare.groovy.j2
+++ b/ci/jenkins/Prepare.groovy.j2
@@ -38,6 +38,7 @@ def init_git() {
     """,
     label: 'Update git submodules',
   )
+  checkout_trusted_files()
 }
 
 def docker_init(image) {
@@ -98,6 +99,30 @@ def cancel_previous_build() {
   }
 }
 
+def checkout_trusted_files() {
+  // trust everything from branch builds
+  if (!env.BRANCH_NAME.startsWith('PR-')) {
+    return;
+  }
+
+  // trust peoople listed in CONTRIBUTING.md
+  grep_code = sh(
+    returnStatus: true,
+    script: "git show '${upstream_revision}:CONTRIBUTORS.md' | grep '@${env.CHANGE_AUTHOR}'",
+    label: 'Check if change is from a contributor',
+  )
+
+  if (grep_code == 1) {
+    // Any scripts that run on the bare host and not inside a Docker container
+    // (especially those that access secrets) should be checked out here so
+    // only trusted versions are used in CI
+    sh(
+      script: "git checkout ${upstream_revision} ci/scripts/.",
+      label: 'Check out trusted files',
+    )
+  }
+}
+
 def should_skip_ci(pr_number) {
   if (env.BRANCH_NAME == null || !env.BRANCH_NAME.startsWith('PR-')) {
     // never skip CI on build sourced from a branch