Hard-coded credentials and command-injection vulnerabilities on BigPond 3G21WB ============================================================================== [ADVISORY INFORMATION] Title: Hard-coded credentials and command-injection vulnerabilities on BigPond 3G21WB Discovery date: 17/09/2012 Release date: 11/10/2012 Credits: Roberto Paleari (roberto@greyhats.it, @rpaleari) [VULNERABILITY INFORMATION] Class: Authentication bypass, command-injection [AFFECTED PRODUCTS] We confirm the following device models to be affected: * BigPond 3G21WB Similar routers are probably vulnerable to these very same issues. [VULNERABILITY DETAILS] The firmware running on the affected routers is subject to multiple security issues that allow an unauthenticated attacker to gain administrative access to the device and execute arbitrary commands. In the following paragraphs we describe the details of the vulnerabilities we identified. a) Hard-coded credentials A user can authenticate to the web server running on the device using the credentials "Monitor:bigpond1". These credentials are hard-coded, and cannot be changed by a normal user. b) Command-injection vulnerability The "ping.cgi" web page is subject to a command-injection vulnerability, as the server-side script does not properly validate user-supplied input. The following URL exploits this issue, executing the "ls /" command: http://<device IP address>/ping.cgi?DIA_IPADDRESS=;%20cat%20/etc/passwd [REMEDIATION] We are not aware of an updated firmware that corrects the issues described in this advisory. We suggest users to disable web access on the WAN side. [DISCLOSURE TIME-LINE] * 17/09/2012 - Initial vendor contact. * 18/09/2012 - Vendor replied asking for details. * 19/09/2012 - The author replied and asked for a technical contact. Disclosure date set to October 10th, 2012 (3 weeks). * 19/09/2012 - Vendor replied, providing the phone contact number of the Technical Support Department. * 20/09/2012 - The author replied, asking to keep all the communication through e-mail, in order to keep track of the whole conversation. * 24/09/2012 - No response from the vendor. The author re-sent the last e-mail. * 04/10/2012 - No response from the vendor. The author re-sent the last e-mail (again). * 11/10/2012 - Still no response from the vendor. Disclosure. [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.