Can the SMS content in mobile phone be partially changed or the whole message be overrided/replaced by another text? The condition is that SMS is a single message (not concatenated message) and message details such as Service Centre address, Originating Address, Service Centre Submission Time Stamp can not be changed. We have seen a case when a message arrived in the handset, it has been changed partially with dirty/insulting words and looks like the changes were intended to be added or replace the original message text. We checked the original content message from traces that flowed from ESME (application), SMPP gateway, SMSC, until MSC are not changed, but when arrived to mobile it has changed partially with the insulting words. We want to see if the possibility of the hack hole in the SMS delivery in the network or if it is done from the user side (mobile phone modification).