Source

File: wp-includes/class-wp-recovery-mode.php

protected function handle_cookie() {
		$validated = $this->cookie_service->validate_cookie();

		if ( is_wp_error( $validated ) ) {
			$this->cookie_service->clear_cookie();

			$validated->add_data( array( 'status' => 403 ) );
			wp_die( $validated );
		}

		$session_id = $this->cookie_service->get_session_id_from_cookie();
		if ( is_wp_error( $session_id ) ) {
			$this->cookie_service->clear_cookie();

			$session_id->add_data( array( 'status' => 403 ) );
			wp_die( $session_id );
		}

		$this->is_active  = true;
		$this->session_id = $session_id;
	}