diff --git a/src/wp-admin/includes/class-wp-privacy-data-export-requests-list-table.php b/src/wp-admin/includes/class-wp-privacy-data-export-requests-list-table.php
index aa68c84649e2f..55438a04594c0 100644
--- a/src/wp-admin/includes/class-wp-privacy-data-export-requests-list-table.php
+++ b/src/wp-admin/includes/class-wp-privacy-data-export-requests-list-table.php
@@ -7,6 +7,11 @@
  * @since 4.9.6
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 if ( ! class_exists( 'WP_Privacy_Requests_Table' ) ) {
 	require_once ABSPATH . 'wp-admin/includes/class-wp-privacy-requests-table.php';
 }
diff --git a/src/wp-admin/includes/class-wp-privacy-data-removal-requests-list-table.php b/src/wp-admin/includes/class-wp-privacy-data-removal-requests-list-table.php
index 716535160f12d..d0a1f5ced345e 100644
--- a/src/wp-admin/includes/class-wp-privacy-data-removal-requests-list-table.php
+++ b/src/wp-admin/includes/class-wp-privacy-data-removal-requests-list-table.php
@@ -7,6 +7,11 @@
  * @since 4.9.6
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 if ( ! class_exists( 'WP_Privacy_Requests_Table' ) ) {
 	require_once ABSPATH . 'wp-admin/includes/class-wp-privacy-requests-table.php';
 }
diff --git a/src/wp-admin/includes/class-wp-upgrader.php b/src/wp-admin/includes/class-wp-upgrader.php
index d641d103864ad..d26002b2772b9 100644
--- a/src/wp-admin/includes/class-wp-upgrader.php
+++ b/src/wp-admin/includes/class-wp-upgrader.php
@@ -9,6 +9,11 @@
  * @since 2.8.0
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /** WP_Upgrader_Skin class */
 require_once ABSPATH . 'wp-admin/includes/class-wp-upgrader-skin.php';
 
diff --git a/src/wp-admin/includes/nav-menu.php b/src/wp-admin/includes/nav-menu.php
index ea7de40a84152..2aae02c39686c 100644
--- a/src/wp-admin/includes/nav-menu.php
+++ b/src/wp-admin/includes/nav-menu.php
@@ -7,6 +7,11 @@
  * @since 3.0.0
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /** Walker_Nav_Menu_Edit class */
 require_once ABSPATH . 'wp-admin/includes/class-walker-nav-menu-edit.php';
 
diff --git a/src/wp-admin/includes/template.php b/src/wp-admin/includes/template.php
index 16da3388aee65..07f8fb8702f01 100644
--- a/src/wp-admin/includes/template.php
+++ b/src/wp-admin/includes/template.php
@@ -8,6 +8,11 @@
  * @subpackage Administration
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /** Walker_Category_Checklist class */
 require_once ABSPATH . 'wp-admin/includes/class-walker-category-checklist.php';
 
diff --git a/src/wp-includes/Requests/library/Requests.php b/src/wp-includes/Requests/library/Requests.php
index 9e42db596b8c9..671c276bf12ba 100644
--- a/src/wp-includes/Requests/library/Requests.php
+++ b/src/wp-includes/Requests/library/Requests.php
@@ -9,4 +9,9 @@
  * @since 6.2.0
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 include_once ABSPATH . WPINC . '/class-requests.php';
diff --git a/src/wp-includes/blocks/require-dynamic-blocks.php b/src/wp-includes/blocks/require-dynamic-blocks.php
index bd1f11608d601..3bc67fc038db7 100644
--- a/src/wp-includes/blocks/require-dynamic-blocks.php
+++ b/src/wp-includes/blocks/require-dynamic-blocks.php
@@ -1,6 +1,12 @@
 <?php
 
 // This file was autogenerated by tools/release/sync-stable-blocks.js, do not change manually!
+
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 // Requires files for dynamic blocks necessary for core blocks registration.
 require_once ABSPATH . WPINC . '/blocks/archives.php';
 require_once ABSPATH . WPINC . '/blocks/avatar.php';
diff --git a/src/wp-includes/cache.php b/src/wp-includes/cache.php
index 5b9259481a90b..791709658952d 100644
--- a/src/wp-includes/cache.php
+++ b/src/wp-includes/cache.php
@@ -8,6 +8,11 @@
  * @subpackage Cache
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /** WP_Object_Cache class */
 require_once ABSPATH . WPINC . '/class-wp-object-cache.php';
 
diff --git a/src/wp-includes/class-simplepie.php b/src/wp-includes/class-simplepie.php
index a8f5c01f08e8a..daa4edba2a640 100644
--- a/src/wp-includes/class-simplepie.php
+++ b/src/wp-includes/class-simplepie.php
@@ -4,6 +4,11 @@
 	return;
 }
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 // Load and register the SimplePie native autoloaders.
 require ABSPATH . WPINC . '/SimplePie/autoloader.php';
 
diff --git a/src/wp-includes/class-wp-customize-section.php b/src/wp-includes/class-wp-customize-section.php
index d2ef51ab0c57f..ac227e9e6aecd 100644
--- a/src/wp-includes/class-wp-customize-section.php
+++ b/src/wp-includes/class-wp-customize-section.php
@@ -7,6 +7,11 @@
  * @since 3.4.0
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /**
  * Customize Section class.
  *
diff --git a/src/wp-includes/meta.php b/src/wp-includes/meta.php
index 6982e618c3d1a..69fad12f4218a 100644
--- a/src/wp-includes/meta.php
+++ b/src/wp-includes/meta.php
@@ -10,6 +10,11 @@
  * @subpackage Meta
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 require ABSPATH . WPINC . '/class-wp-metadata-lazyloader.php';
 
 /**
diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
index d43962988256e..9fd4c88fa51a2 100644
--- a/src/wp-includes/script-loader.php
+++ b/src/wp-includes/script-loader.php
@@ -16,6 +16,11 @@
  * @package WordPress
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /** WordPress Dependency Class */
 require ABSPATH . WPINC . '/class-wp-dependency.php';
 
diff --git a/src/wp-settings.php b/src/wp-settings.php
index f5a0929db87c1..6c7ad8b2351c6 100644
--- a/src/wp-settings.php
+++ b/src/wp-settings.php
@@ -8,6 +8,11 @@
  * @package WordPress
  */
 
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 /**
  * Stores the location of the WordPress directory of functions, classes, and core content.
  *
diff --git a/tools/release/sync-stable-blocks.js b/tools/release/sync-stable-blocks.js
index 3f2a1727d7e3b..25ab503446ae8 100644
--- a/tools/release/sync-stable-blocks.js
+++ b/tools/release/sync-stable-blocks.js
@@ -36,6 +36,7 @@ function main() {
 		`<?php
 
 ${ toolWarningMessage }
+
 // Returns folder names for static blocks necessary for core blocks registration.
 return array(
 ${ staticBlockFolderNames }
@@ -58,6 +59,12 @@ ${ staticBlockFolderNames }
 		`<?php
 
 ${ toolWarningMessage }
+
+// Don't load directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	die( '-1' );
+}
+
 // Requires files for dynamic blocks necessary for core blocks registration.
 ${ dynamicBlockFileRequires }
 `,