Huawei B153 3G/UMTS router WPS weakness ======================================= [ADVISORY INFORMATION] Title: Huawei B153 3G/UMTS router WPS weakness Discovery date: 21/05/2013 Release date: 05/08/2013 Advisory URL: http://blog.emaze.net/2013/08/huawei-b153-3gumts-router-wps-weakness.html Credits: Roberto Paleari (roberto.paleari@emaze.net, @rpaleari) Alessandro Di Pinto (alessandro.dipinto@emaze.net, @adipinto) [VULNERABILITY INFORMATION] Class: Authentication bypass [AFFECTED PRODUCTS] We confirm the presence of the security vulnerability on the following products/firmware versions: * Huawei B153 3G/UMTS router, software version 1096.11.405.03.111sp02 Other device models and firmware versions are probably also vulnerable, but they were not checked. As required by the ISP that distributes this device to end-users, we do not disclose the full commercial name of the product, but only the manufacturer device model (i.e., Huawei B153). [VULNERABILITY DETAILS] To allow wireless users to easily authenticate to the WPA2 Wi-Fi network, the Huawei B153 device supports the WPS procotol [1]. The WPS "External Registrar" PIN-base method is notoriously insecure, as allows attackers to brute force the access PIN in few hours [2]. In the default device configuration, the WPS daemon is configured to accept WPS PIN authentication attempts, but no WPS PIN is configured. Thus, the device is supposed to reject any possible PIN-based WPS request, allowing only the "push button" mechanism, that requires physical interaction. Unfortunately we detected that, despite no WPS PIN is actually configured, a specially-crafted WPS session can still force the device to complete the "External Registrar" handshake, returning to the attacker the current WPA2 passphrase. In other terms attackers located within the wireless range of the device can instantly recover the WPA passphrase. We would also like to stress out that this vulnerability is present in the default device configuration, and no user action is required. This attack cannot be exploited using publicly available tools: no "standard" WPS cracking tool performs handshakes using the specially-crafted WPS session required to exploit this security issue. As a consequence, we implemented our proof-of-concept as a small patch to the reaver WPS cracking tool [3] (the unmodified version of reaver *cannot* recover the password for this device). Footnotes: [1] http://en.wikipedia.org/wiki/Wi-Fi_Protected_Setup [2] http://www.kb.cert.org/vuls/id/723755 [3] https://code.google.com/p/reaver-wps/ [REMEDIATION] Huawei has released an updated firmware version that addresses this issue. [COPYRIGHT] Copyright(c) Emaze Networks S.p.A 2013, All rights reserved worldwide. Permission is hereby granted to redistribute this advisory, providing that no changes are made and that the copyright notices and disclaimers remain intact. [DISCLAIMER] Emaze Networks S.p.A is not responsible for the misuse of the information provided in our security advisories. These advisories are 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.