Cisco IOS XR Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition. Updates are available.
A vulnerability in the Open Shortest Path First version 3 (OSPFv3) implementation in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a crash of the OSPFv3 process on an affected device.
The vulnerability is due to improper parsing of malformed type 1 link-state advertisement (LSA) packets. An attacker could exploit this vulnerability by sending a malformed type 1 LSA packet to a vulnerable device. An exploit could allow the attacker to cause a crash of the OSPFv3 process on an affected device, which may lead to a denial of service (DoS) condition.
Cisco has confirmed the vulnerability in a security notice and released software updates.
At the time this alert was first published, Cisco IOS XR Software version 5.1 was vulnerable. Later releases of Cisco IOS XR Software may also be vulnerable.
To exploit this vulnerability, an attacker may need access to trusted, internal networks, in which such a device would typically be located, to send malformed type 1 LSA packets to. This access requirement decreases the likelihood of a successful exploit.
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-2013-5565
Customers are advised to consult Cisco bug ID CSCuj82176 for a complete list of affected product versions.
An unauthenticated, remote attacker could exploit this vulnerability to crash the OSPFv3 process on an affected device, resulting in a DoS condition.
The vulnerability is due to improper parsing of malformed type 1 LSA packets by an affected device.
An unauthenticated, remote attacker could exploit this vulnerability by sending a malformed type 1 LSA packet to a vulnerable device. An exploit could allow the attacker to cause the OSPFv3 process on an affected device to crash, which may lead to a DoS condition.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
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 email@example.com for assistance.
The security vulnerability applies to the following combinations of products.
Cisco IOS XR Software
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.