diff --git a/wp-admin/includes/class-wp-ms-users-list-table.php b/wp-admin/includes/class-wp-ms-users-list-table.php
index 39dadc788a..962f34aaea 100644
--- a/wp-admin/includes/class-wp-ms-users-list-table.php
+++ b/wp-admin/includes/class-wp-ms-users-list-table.php
@@ -233,7 +233,7 @@ class WP_MS_Users_List_Table extends WP_List_Table {
 	 * @param WP_User $user The current WP_User object.
 	 */
 	public function column_email( $user ) {
-		echo "<a href='mailto:$user->user_email'>$user->user_email</a>";
+		echo "<a href='" . esc_url( "mailto:$user->user_email" ) . "'>$user->user_email</a>";
 	}
 
 	/**
diff --git a/wp-admin/includes/class-wp-users-list-table.php b/wp-admin/includes/class-wp-users-list-table.php
index 4035c58cb6..bb83f85672 100644
--- a/wp-admin/includes/class-wp-users-list-table.php
+++ b/wp-admin/includes/class-wp-users-list-table.php
@@ -435,7 +435,7 @@ class WP_Users_List_Table extends WP_List_Table {
 						$r .= "$user_object->first_name $user_object->last_name";
 						break;
 					case 'email':
-						$r .= "<a href='mailto:$email'>$email</a>";
+						$r .= "<a href='" . esc_url( "mailto:$email" ) . "'>$email</a>";
 						break;
 					case 'role':
 						$r .= $role_name;