3Com OfficeConnect Wireless Cable/DSL Router Authentication Bypass

2009-02-10T00:00:00
ID SECURITYVULNS:DOC:21322
Type securityvulns
Reporter Securityvulns
Modified 2009-02-10T00:00:00

Description

==================================================== Security Research Advisory

Vulnerability name: "3Com OfficeConnect Wireless Cable/DSL Router Authentication Bypass" Advisory number: LC-2008-05 Advisory URL: http://www.ikkisoft.com

==================================================== 1) Affected Hardware/Software

  • 3CRWE554G72 (Hardware version: 3COM_AP51_v01, Software version: 1.2.0 - Nov 14,2006)

Product URL: http://www.3com.com/products/en_US/detail.jsp?tab=features&sku=3CRWE554G72&pathtype=support

Other recent versions, as well as similar 3Com devices, may be affected due to the shared firmware code base.

==================================================== 2) Severity

Severity: Medium Local/Remote: Remote

==================================================== 3) Summary

"The 3Com OfficeConnect Wireless Cable/DSL Router is a high-speed, affordable, and easy-to-use small office solution that lets wireless and wired PCs and laptops securely share a single broadband Internet connection."

This device is very common due to the affordable price and versatility. For these reasons it is widely installed by large telecom providers in all Europe (e.g. In Poland, Orange is currently deploying this device for its residential DSL).

This device is prone to an authentication bypass vulnerability which permits to retrieve the complete system configuration as well as the services credentials (e.g. web console, wifi network).

==================================================== 4) Vulnerability Details

The 3Com OfficeConnect Wireless Cable/DSL Router suffers an authentication bypass vulnerability due to an improper authentication/authorization mechanism.

In order to manage the device, an easy to use web console is enabled by default from the internal network and (optionally) from the Internet. Even if the http daemon does not permit to access HTML pages and the web console without authentication, it is still possible to invoke and execute existent CGI programs. Unfortunately, the "System Tools-->Configuration-->Backup Configuration" functionality saves the actual system configuration in a persistent plain-text file named "config.bin" using a custom CGI program. An unauthenticated user may directly invoke the "SaveCfgFile" CGI program and easily download the system configuration containing configuration information, users, passwords, wifi keys and other sensitive information.

Note: if the "Remote Administration" option is enabled, this vulnerability may be exploited from the Internet as well.

Example of sensitive content within the "config.bin" file: [...] pppoe_username=xxxxxxxxxxxxxxx pppoe_password=xxxxxxxxx pppoe_service_name=xxxxxxxxx [...] mradius_username=xxxxxx mradius_password=xxxxxx mradius_secret=xxxxxxx [...] http_username=xxxxx login_password=xxxxx http_passwd=xxxxx [...] AuthName=xxxxxxx AuthPassword=xxxx snmpStatus=xxxxxxx snmpRoCommunity=xxxxxxxx snmpRwCommunity=xxxxxxxx [...] multi_dmz_wan_ip1=xxxxxxxxxx [...] lan_macaddr=xxxxxxxxxxxxx [...]

Later on, looking for similar vulnerabilities in the Bugtraq database, I've found a similar finding discovered by Patrik, cqure.net (iDEFENSE Security Advisory 01.20.05). As far as I know and I can understand from the firmware versions reported, this issue seems to be a further authentication bypass technique due to an insufficient patch supplied by the vendor.

==================================================== 5) Exploit

Attackers may exploit this flaw through a common web browser.

http://<IP>/SaveCfgFile.cgi

==================================================== 6) Fix Information

To reduce the overall exploitability, disable the "Remote Administration" option. However, a firmware update is required in order to resolve this issue.

==================================================== 7) Time Table

08/12/2008 - Vendor notified via "3Com Vulnerability Disclosure Form" ??/??/???? - Vendor response. ??/??/???? - Vendor patch release. 09/02/2009 - Public disclosure.

==================================================== 8) Credits

Discovered by Luca Carettoni - luca.carettoni[at]ikkisoft[dot]com

==================================================== 9) Legal Notices

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. There are no warranties with regard to this information. The author does not accept any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information. Permission is hereby granted for the redistribution of this alert, provided that the content is not altered in any way, except reformatting, and that due credit is given.

This vulnerability has been disclosed in accordance with the RFP Full-Disclosure Policy v2.0, available at: http://www.wiretrip.net/rfp/policy.html

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