Special characters automatically gets returned - Red Hat Enterprise Linux Server release 7.0

Linux and Unix-Like Red Hat
1

Dear experts,

We are using Linux OS i.e Red Hat Enterprise Linux Server release 7.0

I log to the server using putty & default shell is

Code:
-bash4.2$ echo $SHELL /bin/bash

special character automatically gets returned in my putty.

Code:
-bash-4.2$ ~

Also this special character gets returned to the Oracle database running on the server

Code:
SQL>^[[28~

It's weird because it affects badly our work & this happens even we open files using an editor using 'vi' as well.

Appreciate your reply.