Advisory ID: cisco-sa-20010614-nrp2-telnet
For Public Release 2001 June 14 15:00 UTC (GMT)
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
This section provides details on affected products.
Cisco 6400 NRP2 modules running Cisco IOS® release earlier than
12.1(05)DC01 are affected by this vulnerability.
To determine your software revision, type show
version at the command line prompt.
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
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.
Cisco has provided scores for the vulnerabilities in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0.
CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response.
Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks.
Cisco has provided an FAQ to answer additional questions regarding CVSS at
Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at
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.
This vulnerability has been fixed in Cisco IOS release 12.1(05)DC01 or
Apply password to all the 32 vtys on the NRP2.
Enable Prompt> vty 0 31 password
Cisco has made free software available to address this vulnerability
for affected customers. Prior to deploying software, customers should consult
their maintenance provider or check the software for feature set compatibility
and known issues specific to their environment.
Customers may only install and expect support for the feature sets they
have purchased. By installing, downloading, accessing or otherwise using such
software upgrades, customers agree to be bound by the terms of Cisco's software
license terms found at
or as otherwise set forth at Cisco.com Downloads at
Do not contact either "firstname.lastname@example.org" or "email@example.com"
for software upgrades.
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 website 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 guidance and assistance with the appropriate course of
action in regards to this advisory.
The effectiveness of any workaround or fix is dependent on specific
customer situations such as product mix, network topology, traffic behavior,
and organizational mission. Due to the variety of affected products and
releases, customers should consult with their service provider or support
organization to ensure any applied workaround or fix is the most appropriate
for use in the intended network before it is deployed.
Customers who purchase direct from Cisco but who do not hold a Cisco
service contract and customers who purchase through third-party vendors but are
unsuccessful at obtaining fixed software through their point of sale 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)
Have your product serial number available and 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.
for additional TAC contact information, including special localized telephone
numbers and instructions and e-mail addresses for use in various
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.
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors.
This advisory will be posted on Cisco's worldwide website 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.
firstname.lastname@example.org (includes CERT/CC)
Various internal Cisco mailing lists
Future updates of this advisory, if any, will be placed on Cisco's
worldwide website, but may or may not be actively announced on mailing lists or
newsgroups. Users concerned about this problem are encouraged to check the
above URL for any updates.
Initial public release.