ChatNess 2.5 Session Fixation

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#  
# Exploit Title: ChatNess 2.5 Session Fixation Script  
# Date: 2014 18 March  
# Author: Dr.3v1l  
# Vendor Homepage: http://www.chatness.us  
# Version : 2.5  
# Tested on: Windows  
# Category: webapps  
# Google Dork: intext:"Powered by Chatness"  
#  
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#  
# [+] Exploit :  
#  
# http://<server>/chatness/chatness/chat.php  
#  
# Discovered by: Scripting (Session_Fixation.script).  
#   
# Attack details :  
# Session cookie PHPSESSID was fixed to acunetixsessionfixation.  
#   
# Vulnerability description :  
#  
# Session Fixation is an attack that permits an attacker to hijack a valid user session.  
# The attack explores a limitation in the way the web application manages the session ID,  
# more specifically the vulnerable web application. When authenticating a user,  
# it doesn't assign a new session ID, making it possible to use an existent session ID.  
# The attack consists of inducing a user to authenticate himself with a known session ID,  
# and then hijacking the user-validated session by the knowledge of the used session ID.  
# The attacker has to provide a legitimate Web application session ID and try to make the victim's browser use it.  
#  
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#  
# [+] Contact Me :  
#  
# [email protected]  
# Twitter.com/Doctor_3v1l  
# Facebook.com/bdb.0web  
# Facebook.com/groups/1427166220843499/  
# IR.linkedin.com/in/hossein3v1l  
# Hossein Hezami - Black_Devils B0ys  
#  
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# B.Devils.B Friends , R.H.H (UnderGround) , IeDB.IR , IrSecTeam  
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