I - TITLE

Security advisory: Arbitrary file disclosure vulnerability in
rrdbrowse

II - SUMMARY

Description: Arbitrary file disclosure vulnerability in
rrdbrowse <= 1.6

Author: Sebastian Wolfgarten (sebastian at wolfgarten dot com),
http://www.devtarget.org

Date: March 4th, 2007

Severity: Medium

References: http://www.devtarget.org/rrdbrowse-advisory-03-2007.txt

III - OVERVIEW

Quote from rrdbrowse.org: "RRDBrowse is a poller daemon, templater and
webinterface for RRDTool. It has a threaded daemon which periodically
runs from cron. It works with small .nfo files which hold router
information and optionally connection details, colors, min max,
bandwidth settings, etc, etc. RRDBrowse uses a small caching mechanism
to store interface names. It's much MRTG like in it's current state".
More information about the product can be found online at
http://www.rrdbrowse.org.

IV - DETAILS

Due to inproper input validation, the CGI application "rrdbrowse"
(versions <=1.6) is vulnerable to an arbitrary file disclosure
vulnerability. It allows an unauthenticated remote attacker to read any
file on the remote system if the user the webserver is running as has
permissions to do so. Thus an attacker is able to gain access
potentially sensitive information.

V - EXPLOIT CODE

The vulnerability is trivial to exploit and only requires specifying an
URL with a relative file path on the remote system such as

http://$target/cgi-bin/rb.cgi?mode=page&file=../../../../../../../../etc/passwd

As the input to the "file" parameter is not validated in any way
accessing this URL will expose the contents of /etc/passwd to a remote
attacker (interestingly except the first line).

VI - WORKAROUND/FIX

To address this problem, the author of rrdbrowse (Tommy van Leeuwen) has
released an updated CVS version (1.7) of the software which is available
at http://www.rrdbrowse.org. Hence all users of rrdbrowse are asked to
test and install this version as soon as possible.

VII - DISCLOSURE TIMELINE

06. February 2007 - Notified vendor
14. Feburary 2007 - Patch/new version released
04. March 2007 - Public disclosure

# milw0rm.com [2007-03-04]