	wp.updates.updateThemeError = function( response ) {
		var $theme       = $( '[data-slug="' + response.slug + '"]' ),
			errorMessage = wp.updates.l10n.updateFailed.replace( '%s', response.errorMessage ),
			$notice;

		if ( ! wp.updates.isValidResponse( response, 'update' ) ) {
			return;
		}

		if ( wp.updates.maybeHandleCredentialError( response, 'update-theme' ) ) {
			return;
		}

		if ( 'themes-network' === pagenow ) {
			$notice = $theme.find( '.update-message ' );
		} else {
			$notice = $( '.theme-info .notice' ).add( $theme.find( '.notice' ) );

			$( 'body.modal-open' ).length ? $( '.load-customize:visible' ).focus() : $theme.find( '.load-customize' ).focus();
		}

		wp.updates.addAdminNotice( {
			selector:  $notice,
			className: 'update-message notice-error notice-alt is-dismissible',
			message:   errorMessage
		} );

		wp.a11y.speak( errorMessage, 'polite' );

		$document.trigger( 'wp-theme-update-error', response );
	};
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.