Web - Client

Hello, someone please help me. I try to decide this task for two days.
I have a web server with logs. And I write a js code to message field, it redirect throw the image admin cookie, but I don’t give its in my web site.
Uncommonly, after i post my message, i give the next message : "Vos messages ont bien été lus / Your messages have been read". How I can right get cookie.?Thanks.