Unauthenticated remote access to D-Link DIR-645 devices
=======================================================

[ADVISORY INFORMATION]
Title:    Unauthenticated remote access to D-Link DIR-645 devices
Discovery date: 20/02/2013
Release date:   27/02/2013
Credits:        Roberto Paleari (roberto@greyhats.it, twitter: @rpaleari)

[VULNERABILITY INFORMATION]
Class:           Authentication bypass

[AFFECTED PRODUCTS]
This security vulnerability affects the following products and firmware
versions:
   * D-Link DIR-645, firmware version < 1.03
Other products and firmware versions could also be vulnerable, but they were
not checked.

[VULNERABILITY DETAILS]
The web interface of D-Link DIR-645 routers expose several pages accessible
with no authentication. These pages can be abused to access sensitive
information concerning the device configuration, including the clear-text
password for the administrative user. In other words, by exploiting this
vulnerability unauthenticated remote attackers can retrieve the administrator
password and then access the device with full privileges.

More in detail, the following HTTP request fetches the administrator password:
     curl -d SERVICES=DEVICE.ACCOUNT http://<device ip>/getcfg.php

For those that are not familiar with "curl" syntax, the above command-line
requests the "getcfg.php" page, supplying the HTTP POST data
"SERVICES=DEVICE.ACCOUNT".

The lack of proper authentication checks is not limited to the "getcfg.php" web
page. As an example, the following requests can also be performed with no
authentication:
1. Read system log
   curl http://<device ip>/log_get.php

2. Get DDNS statistics
   curl -d act=getreport http://<device ip>/ddns_act.php

3. Dump device details
   curl http://<device ip>/DevInfo.php

[REMEDIATION]
D-Link has released an updated firmware version (1.03) that addresses this
issue. The firmware is already available on D-Link web site, and introduces
additional restrictions to forbid unauthenticated access to page "getcfg.php".

[DISCLAIMER]
The author is not responsible for the misuse of the information provided in
this security advisory. The advisory is a service to the professional security
community. There are NO WARRANTIES with regard to this information. Any
application or distribution of this information constitutes acceptance AS IS,
at the user's own risk. This information is subject to change without notice.