A vulnerability in the Internet Security Association and Key Management Protocol (ISAKMP) implementation in Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to enumerate remote access VPN groups configured in a Cisco ASA device. The vulnerability is due to differences in the way Cisco ASA Software responds to Internet Key Exchange (IKE) aggressive mode messages when valid and invalid VPN groups are provided in the AM1 message. An attacker could exploit this vulnerability by sending crafted IKE messages to a Cisco ASA device that is configured as a VPN headend. This vulnerability was discovered by Daniel Turner of Trustwave SpiderLabs. Cisco would like to thank Trustwave SpiderLabs for reporting this issue and working with us toward coordinated disclosure of this vulnerability. Cisco has confirmed the vulnerability in a security notice and software updates are available. To exploit the vulnerability, an attacker may need access to trusted, internal networks to send crafted IKE messages to the targeted system. This access requirement may reduce the likelihood of a successful attack. Customers are advised to review the bug report in the vendor announcements section for a current list of affected versions. Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
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.
Version | Description | Section | Status | Date |
1.0 | Initial Release | NA | Final | 2013-Apr-18 |
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.