Upgrade to PHP 5.6 Ubuntu 14.04
Kindly use this command
sudo add-apt-repository ppa:ondrej/php
sudo apt-get update
sudo apt-get -y install php5.6 php5.6-mcrypt php5.6-mbstring php5.6-curl php5.6-cli php5.6-mysql php5.6-gd php5.6-intl php5.6-xsl php5.6-zip