Netvolution CMS v2.5.8 is vulnerable to a blind SQL injection attack
in the HTTP “referer” header. A malicious user may utilize this
vulnerability to modify content on the vulnerable website, inject
malicious javascript code to a visitor’s browser, collect CMS usernames
and plaintext passwords and, in some cases, execute commands on the
system hosting the database server. This is a critical vulnerability
since it does not require authentication and its exploitation may go
undetected.

Netvolution [1] is a commercial content management system by
ATCOM S.A. [2] with a large number of installations, most of them
belonging to Greek companies and organizations.

It appears that the Netvolution platform has both ASP and PHP
implementations. This advisory concerns a bug found in the ASP
implementation (version 2.5.8). We were unable to verify with the
vendor if this bug also affects other versions of the ASP (or PHP)
codebase.

The bug is located in the code that parses the “HTTP Referer” header
value. An attacker may inject arbitrary SQL commands to the Netvolution
database by using a “Referer” header like the following:

Referer: 1','0'); SQL

In the above example “SQL” is a placeholder; the attacker would replace
this with the SQL commands to be executed by the database server.
The CMS does not provide feedback on the output of the SQL commands
but collection of this output is still possible through “blind” SQL
Injection techniques.

More information about this vulnerability and a Proof of Concept
are available here [3].

As header field values are normally not included in HTTP transaction
logs, an attack based on this vulnerability may go unnoticed by web
server administrators.

We have repeatedly contacted the software vendor about this issue but
we have not received a reply.

Administrators of Netvolution websites are advised to check with the
software vendor to ensure that they are running a non-vulnerable
version of the CMS.

The Common Vulnerabilities and Exposures (CVE) project has assigned
the candidate name CVE-2011-3340 to this issue.

Disclosure Timeline
-------------------
CVE assignment:    August 30th, 2011
Vendor Contact(s): August 31st, 2011
                   September 1st, 2011
                   September 27th, 2011
Public Disclosure: October 3rd, 2011

Credits
-------
Vulnerability discovered by: Patroklos Argyroudis
Research & Exploitation by: Dimitris Glynos

Kind regards,

Dimitris Glynos
--
http://census-labs.com -- IT security research, development and services

[1] http://netvolution.net
[2] http://atcom.gr
[3] http://census-labs.com/news/2011/10/03/netvolution-referer-SQLi/