Ticket #42238: 42238.diff

src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php

@@ -1592 +1592 @@
          * @return bool Whether post can be read.
          */
         protected function check_read_post_permission( $post, $request ) {
-                $post_type        = get_post_type_object( $post->post_type );
+                $post_type = get_post_type_object( $post->post_type );
+
+                // Return false if custom post type doesn't exist
+                if ( ! $post_type ) {
+                        return false;
+                }
+
                 $posts_controller = $post_type->get_rest_controller();
 
                 // Ensure the posts controller is specifically a WP_REST_Posts_Controller instance

tests/phpunit/tests/rest-api/rest-comments-controller.php

@@ -3240 +3240 @@
                         $this->assertArrayNotHasKey( 'raw', $data['content'] );
                 }
         }
+
+        /**
+         * @ticket 42238
+         */
+        public function test_check_read_post_permission_with_invalid_post_type() {
+                register_post_type(
+                        'bug-post',
+                        array(
+                                'label'        => 'Bug Posts',
+                                'supports'     => array( 'title', 'editor', 'author', 'comments' ),
+                                'show_in_rest' => true,
+                                'public'       => true,
+                        )
+                );
+                create_initial_rest_routes();
+
+                $post_id    = self::factory()->post->create( array( 'post_type' => 'bug-post' ) );
+                $comment_id = self::factory()->comment->create( array( 'comment_post_ID' => $post_id ) );
+                _unregister_post_type( 'bug-post' );
+
+                $this->setExpectedIncorrectUsage( 'map_meta_cap' );
+
+                wp_set_current_user( self::$admin_id );
+                $request  = new WP_REST_Request( 'GET', '/wp/v2/comments/' . $comment_id );
+                $response = rest_get_server()->dispatch( $request );
+                $this->assertEquals( 403, $response->get_status() );
+        }
 }