Pop up message customization in sccm 2012

Hi Experts,

We are in a need from customer stating the pop message need to be cusotmized. 

I had checked in SCCM to customize the pop up message but unable to find. 

Kindly let me know is there a way to cusotmize the pop up message in SCCM 2012 with out using script / 3rd party software. 

Thanks in advance.

Regards,

Ranjith