Advisory ID: cisco-sa-20031210-ACNS-auth
For Public Release 2003 December 10 16:00 UTC (GMT)
By entering an overly long password, it may be possible to execute arbitrary code on a vulnerable device. This vulnerability affects all devices and hardware modules that are running ACNS software releases prior to 4.2.11 and 5.0.5. The workaround is to disable the CE GUI server.
This advisory will be available at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20031210-ACNS-auth.
All Cisco products running ACNS software versions prior to 4.2.11 or 5.0.5 are affected. The hardware models that supports ACNS are:
- Content Routers 4400 series
- Content Distribution Manager 4600 series
- Content Engine 500 and 7300 series
- Content Engine Module for Cisco Routers 2600, 3600 and 3700 series
ACNS version 5.1 is not affected by these vulnerabilities
No other Cisco products are currently known to be affected by these vulnerabilities.
By supplying an overly long password, it is possible to trigger a buffer overflow in the authentication module. This may enable an attacker to execute arbitrary code on the affected device.
This vulnerability is assigned Cisco bug IDs CSCeb25596 (registered customers only) and CSCeb27087 (registered customers only).
Cisco has not provided scores for the vulnerabilities in this advisory based on the Common Vulnerability Scoring System (CVSS). At the time of original publication, CVSS scoring in Cisco security publications was not yet adopted.
The impact of the exploitation of this vulnerability can range from a Denial-of-Service to complete control of the device.
This vulnerability is fixed in 4.2.11 and 5.0.5 releases of ACNS.
When considering software upgrades, also consult http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution.
In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance.
The workaround is to disable the CE GUI server using the following command:
no gui-server enable
Cisco has released free software updates that address these vulnerabilities. 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 email@example.com or firstname.lastname@example.org 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 agreements 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 do not hold a Cisco service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should acquire 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: email@example.com
Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC.
Refer to http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, and instructions and e-mail addresses for use in various languages.
The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory.
This vulnerability was discovered during internal testing.
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 is 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.
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.