Cisco Security Advisory
Click Icon to Copy Verbose Score
AV:N/AC:L/Au:N/C:N/I:P/A:N/E:F/RL:OF/RC:C
-
A vulnerability in the implementation of the Cisco IOS Software Internet Key Exchange version 2 (IKEv2) protocol may cause the anti-replay capabilities of IPsec to be disabled. This issue occurs only when using the Advanced Encryption Standard Galois/Counter Mode (AES-GCM) or the AES Galois Message Authentication Code (AES-GMAC) algorithms for Phase 2 IPsec Security Associations (SAs).
The vulnerability is due to improper coding of the logic required to enable or disable the anti-replay capabilities of an IPsec Phase 2 SA. An attacker could exploit this vulnerability by sending traffic that will traverse an IPsec tunnel. An exploit could allow the attacker to replay previously sent traffic as long as the application consuming the traffic does not implement its own sequence or anti-replay checks. Neither the confidentiality nor the authentication capabilities of IPsec are affected by this vulnerability.
Cisco has confirmed the vulnerability in a security notice and released software updates.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
-
Customers are advised to consult Cisco bug ID CSCuj47795 for the most complete list of affected product versions.
-
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 tac@cisco.com for assistance.
-
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
-
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
-
Show LessVersion Description Section Status Date 1.0 Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to modify the anti-replay capabilities of IPsec on a targeted device. Updates are available. NA Final 2013-Oct-30
-
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 is an uncontrolled copy, and may lack important information or contain factual errors. The information in this document is intended for end-users of Cisco products.