SEC Consult Vulnerability Lab Security Advisory < 20220113-0 > ======================================================================= title: Cleartext Storage of Phone Password product: Cisco IP Phone Series 78x1, 88x5, 88x1, 7832, 8832, 8821 and 3905 vulnerable version: Firmware <14.1.1, Firmware <11.0(6)SR2 (device model 8821), Firmware <9.4(1)SR5 (device model 3905) fixed version: Firmware 14.1.1, 11.0(6)SR2, 9.4(1)SR5 CVE number: CVE-2022-20660 impact: Medium homepage: https://www.cisco.com found: 2021-04-15 by: Gerhard Hechenberger (Office Vienna) Steffen Robertz (Office Vienna) SEC Consult Vulnerability Lab An integrated part of SEC Consult, an Atos company Europe | Asia | North America https://www.sec-consult.com ======================================================================= Vendor description: ------------------- "The Cisco® IP Phone 7800 Series is a cost-effective, high-fidelity voice communications portfolio designed to improve your organization’s people-centric communications, while reducing your operating costs. It combines an attractive new ergonomic design with “always-on” reliability and secure encrypted communications. The Cisco® IP Phone 7800 Series delivers advanced IP Telephony features and crystal clear wideband audio performance to deliver an easy-to-use, full-featured voice communications experience on Cisco on-premises and hosted infrastructure platforms and third party hosted call control." Source: https://www.cisco.com/c/en/us/products/collateral/collaboration-endpoints/unified-ip-phone-7800-series/data-sheet-c78-729488.html Business recommendation: ------------------------ SEC Consult recommends to update the devices to the newest firmware listed below, where, according to the vendor, the documented issue is fixed. We want to thank Cisco for the very professional response and great coordination. Vulnerability overview/description: ----------------------------------- 1) Cleartext Storage of Phone Password The phone is storing the "phone password", which is needed to access its administrative settings, in cleartext (in multiple locations) in the flash memory. Because the password is not hashed using a suitable cryptographic hash function and the storage is unencrypted, a physical attacker can easily recover the password and reuse it on other phones, if they are not configured to use unique administrative passwords. Proof of concept: ----------------- 1) Cleartext Storage of Phone Password Steps to take: - Configure a phone password via the TFTP XML provisioning feature. - Desoldering the memory and reading its content. - Analyzing the memory content. As example, the Linux command 'strings' can be used below to show the identified password in cleartext in the dumped data. ---------------------------------------- $ strings nand.dump | grep phonePassword phonePassword>sectestsectestsectestsectest