Secure Network - Security Research Advisory
Vuln name: [Siemens SANTIS 50 Authentication Vulnerability]
Systems affected:
Siemens Santis 50 Wireless router (firmware version: 4.2.8.0)
Likely to be affected:
Ericsson HN294dp
Dynalink RTA300W
Severity: medium risk
Local/Remote: Remote (limited to the LAN, with default configuration)
Vendor URL: http://www.dynalink.com.au/modemsadsl_dis.htm?prod=RTA300W#
http://help.virgilio.it/guide/index.jsp?
id=5080&id_figlio=5541 (italian Internet provider)
Author(s): Luca Carettoni - luca.carettoni@securenetwork.it
Vendor disclosure: 17th July 2005
Vendor acknowledged: Not acknowledged
Public disclosure: 25th July 2005
Advisory number: SN-2005-01
Advisory URL: http://www.securenetwork.it/advisories/
*** SUMMARY ***
The Siemens Santis 50 Wireless router is a wi-fi (802.11b) ADSL router. It's a
complete system for home and small business networks in a single device.
Some features include:
- Integrated WLAN for internet sharing
- ADSL Modem/Router/Firewall/Switch
- 10/100 Mbps 4 port switch built in
- Stateful packet inspection (SPI) firewall
- Wireless Access Point
- VPN passthrough
Telecom Italia Net (one of the largest italian Internet providers) delivers
this device to its ADSL customers, so in Italy it's a common device used in
SOHO and SMB networks.
The Siemens Santis50, the Ericsson HN294dp and the Dynalink RTA300W devices
share the same hardware, so it's very likely that they share this
vulnerability. The original project of these products was from Askey. The
firmware software is from VirataGlobespan, bought by Conexant.
The tested (vulnerable) version of firmware is the 4.2.8.0
This bug provides access to the management CLI, without authentication, after
a DOS attack to a specific service port.
*** VULNERABILITY DETAILS ***
This device provides a web management interface and the classic telnet CLI for
administration purposes. By default these services are available only from the
local network, but can be optionally activated also on the WAN interface.
Sending trigger packets to the management port (280/http-mgmt), the device
"freezes" the web interface, allowing unauthenticated connection to the telnet
CLI.
This behavior appears to be some sort of "disaster recovery mode". The set of
available commands is limited to a few, but they are enough to discover
informations about the configuration of the device and connections (events,
traffic, ethernet addresses configuration, etc). Also critical commands like
"irreversibly erase FLASH contents" are available.
*** EXPLOIT ***
A simple exploit is to use the application scanner AMAP (kudos to THC,
www.thc.org).
Mojito:~ LuCa$ amap x.x.x.x 280
*** FIX INFORMATION ***
A vendor-provided fix is currently unavailable. An upgrade to a more recent
version of firmware (v5.2.2 is currently available) could help, but we are
unable to test this version.
An obvious workaround (and good practice) is to disable the management
interface on the WAN, this obviously blocks this attack from external attackers.
*********************
*** LEGAL NOTICES ***
*********************
Secure Network (www.securenetwork.it) is an information security company,
which provides consulting and training services, and engages in security
research and development.
We are committed to open, full disclosure of vulnerabilities, cooperating
with software developers for properly handling disclosure issues.
This advisory is copyright © 2005 Secure Network S.r.l. Permission is
hereby granted for the redistribution of this alert, provided that it is
not altered except by reformatting it, and that due credit is given. It
may not be edited in any way without the express consent of Secure Network
S.r.l. Permission is explicitly given for insertion in vulnerability
databases and similars, provided that due credit is given to Secure Network
The information in the advisory is believed to be accurate at the time of
publishing based on currently available information. This information is
provided as-is, as a free service to the community by Secure Network
research staff. There are no warranties with regard to this information.
Secure Network does not accept any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.
If you have any comments or inquiries, or any issue with what is reported
in this advisory, please inform us as soon as possible.
E-mail: securenetwork@securenetwork.it
GPG/PGP key: http://www.securenetwork.it/pgpkeys/Secure%20Network.asc
Phone: +39 0363 560 402
