Index: src/wp-admin/includes/template.php
===================================================================
--- src/wp-admin/includes/template.php	(revision 31667)
+++ src/wp-admin/includes/template.php	(working copy)
@@ -1054,7 +1054,54 @@
 						echo '<div class="handlediv" title="' . esc_attr__('Click to toggle') . '"><br /></div>';
 					echo "<h3 class='hndle'><span>{$box['title']}</span></h3>\n";
 					echo '<div class="inside">' . "\n";
-					call_user_func($box['callback'], $object, $box);
+
+					/**
+					 * Fires first thing inside the meta_box content
+					 *
+					 * @since 4.1.2
+					 *
+					 * @param mixed $object The full object. Could be a post, user, comment (etc) object
+					 * @param array $box    Array of meta_box parameters
+					 */
+					do_action( 'before_meta_box_callback', $object, $box );
+
+					/**
+					 * Fires first thing inside the meta_box content
+					 *
+					 * The dynamic portion of the hook name, `$box['id']`, is the id of the registered meta_box.
+					 *
+					 * @since 4.1.2
+					 *
+					 * @param mixed $object The full object. Could be a post, user, comment (etc) object
+					 * @param array $box    Array of meta_box parameters
+					 */
+					do_action( "before_{$box['id']}_meta_box_callback", $object, $box );
+
+					// Fire off the registered meta box callback function
+					call_user_func( $box['callback'], $object, $box );
+
+					/**
+					 * Fires last inside the meta_box content
+					 *
+					 * @since 4.1.2
+					 *
+					 * @param mixed $object The full object. Could be a post, user, comment (etc) object
+					 * @param array $box    Array of meta_box parameters
+					 */
+					do_action( 'after_meta_box_callback', $object, $box );
+
+					/**
+					 * Fires last inside the meta_box content
+					 *
+					 * The dynamic portion of the hook name, `$box['id']`, is the id of the registered meta_box.
+					 *
+					 * @since 4.1.2
+					 *
+					 * @param mixed $object The full object. Could be a post, user, comment (etc) object
+					 * @param array $box    Array of meta_box parameters
+					 */
+					do_action( "after_{$box['id']}_meta_box_callback", $object, $box );
+
 					echo "</div>\n";
 					echo "</div>\n";
 				}