Cisco IOS XE Software contains a vulnerability that could allow an authenticated, remote attacker to cause a denial of service condition. Updates are available.
A vulnerability in the Layer 2 Tunneling Protocol (L2TP) module of Cisco IOS XE on Cisco ASR 1000 Series Routers could allow an authenticated, remote attacker to cause a reload of the processing ESP card.
The vulnerability occurs during the processing of a malformed L2TP packet. An attacker could exploit this vulnerability by sending malformed L2TP packets over an established L2TP session. An exploit could allow the attacker to cause a reload of the affected ESP card.
Cisco has confirmed the vulnerability in a security notice and released software updates.
At the time this alert was first published, Cisco IOS XE Software versions 3.10S(.2) and prior were vulnerable. Later releases of Cisco IOS XE Software may also be vulnerable.
To exploit this vulnerability, an attacker must authenticate to a targeted device. This access requirement decreases the likelihood of a successful exploit attempt.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
Cisco has released a security notice at the following link: CVE-2014-2183
Customers are advised to consult Cisco bug ID CSCun09973 for a complete list of affected product versions.
An authenticated, remote attacker could exploit this vulnerability to cause the ESP card on an affected device to reload, resulting in a denial of service (DoS) condition.
The vulnerability is due to improper processing of malformed L2TP packets by a device running an affected version of Cisco IOS XE Software.
An authenticated, remote attacker could exploit this vulnerability by sending malformed L2TP packets over an established L2TP session to a targeted device. An exploit could allow the attacker to cause a reload of the affected ESP card on the targeted device, resulting in a DoS condition.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators are advised to monitor affected systems.
Cisco customers with active contracts should contact their Cisco support team for assistance in upgrading to a software version that includes fixes for this vulnerability. Cisco customers without contracts may contact the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via email at firstname.lastname@example.org for assistance.
The security vulnerability applies to the following combinations of products.
Cisco IOS XE Software
3.10S .0, .0a, .1, .2
The urgency and severity ratings of this alert are not tailored to individual users; users may value alerts differently based upon their network configurations and circumstances. THE ALERT, AND INFORMATION CONTAINED THEREIN, ARE PROVIDED ON AN "AS IS" BASIS AND DO NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE ALERT, AND INFORMATION CONTAINED THEREIN, OR MATERIALS LINKED FROM THE ALERT, IS AT YOUR OWN RISK. INFORMATION IN THIS ALERT AND ANY RELATED COMMUNICATIONS IS BASED ON OUR KNOWLEDGE AT THE TIME OF PUBLICATION AND IS SUBJECT TO CHANGE WITHOUT NOTICE. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE ALERTS AT ANY TIME.