Cisco Systems Inc. Affected

Updated:  September 20, 2001



Vendor Statement

Please see A copy of that document is included below.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


Cisco Security Advisory: Cisco 6400 NRP2 Telnet Vulnerability Revision 1.0 For Public Release 2001 June 14 at 1500 UTC Please provide your feedback on this document. Summary The Cisco 6400 Access Concentrator Node Route Processor 2 (NRP2) module allows Telnet access when no password has been set. The correct response is to disallow any remote access to the module until the password has been set. This vulnerability may result in users gaining unintended access to secure systems. This vulnerability is documented as Cisco bug ID CSCdt65960. This advisory will be posted at Affected Products Cisco 6400 NRP2 modules running Cisco IOS® release earlier than 12.1(05)DC01 are affected by this vulnerability. Cisco 6400 NSP and Cisco 6400 NRP1 modules are not affected by this vulnerability. No other Cisco product is currently known to be affected by this vulnerability. To determine your software revision, type show version at the command line prompt. Details The Cisco 6400 Access Concentrator NRP2 module allows Telnet access when no password is set for the vtys on the NRP2. This vulnerability affects the Gigabit Ethernet, ATM and Serial interface on the NRP2. The correct response is to not allow any remote access to the module until the vty password has been set. This vulnerability is documented as Cisco bug ID CSCdt65960, which requires a CCO account to view. Impact A user can gain access to secure systems if the initial vtys have not had their password set. This vulnerability can be eliminated by applying the workaround or by upgrading the IOS. Software Versions and Fixes This vulnerability has been fixed in Cisco IOS release 12.1(05)DC01 or later. Obtaining Fixed Software Cisco is offering free software upgrades to eliminate this vulnerability for all affected customers. Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's Worldwide Web site at Customers whose Cisco products are provided or maintained through prior or existing agreement with third-party support organizations such as Cisco Partners, authorized resellers, or service providers should contact that support organization for assistance with the upgrade, which should be free of charge. Customers without contracts should get their upgrades by contacting the Cisco Technical Assistance Center (TAC). TAC contacts are as follows: * +1 800 553 2447 (toll-free from within North America) * +1 408 526 7209 (toll call from anywhere in the world) * e-mail: Give the URL of this notice as evidence of your entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC. Please do not contact either "" or "" for software upgrades. Workarounds Apply password to all the 32 vtys on the NRP2. Enable Prompt>  vty 0 31 password "the-password" Exploitation and Public Announcements The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities described in this advisory. This vulnerability was reported to Cisco by a Cisco customer. Status of This Notice: FINAL This is a final PSIRT advisory. Although Cisco cannot guarantee the accuracy of all statements in this notice, all of the facts have been checked to the best of our ability. Cisco does not anticipate issuing updated versions of this advisory unless there is some material change in the facts. Should there be a significant change in the facts, Cisco may update this advisory. Distribution This notice will be posted on Cisco's Worldwide Web site at In addition to Worldwide Web posting, a text version of this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the following e-mail and Usenet news recipients: * * * (includes CERT/CC) * * * * * Various internal Cisco mailing lists Future updates of this notice, if any, will be placed on Cisco's Worldwide Web server, but may or may not be actively announced on mailing lists or newsgroups. Users concerned about this problem are encouraged to check the URL given above for any updates. Revision History Revision 1.0 June 14, 2001 Initial public release Cisco Security Procedures Complete information on reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco, is available on Cisco's Worldwide Web site at This includes instructions for press inquiries regarding Cisco security notices. This notice is Copyright 2001 by Cisco Systems, Inc. This notice may be redistributed freely after the release date given at the top of the text, provided that redistributed copies are complete and unmodified, and include all date and version information.