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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2017.0694 Cisco Adaptive Security Appliance BGP Bidirectional Forwarding Detection ACL Bypass Vulnerability 16 March 2017 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Cisco Adaptive Security Appliance Publisher: Cisco Systems Operating System: Cisco Impact/Access: Unauthorised Access -- Remote/Unauthenticated Resolution: Mitigation CVE Names: CVE-2017-3867 Original Bulletin: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170315-asa - --------------------------BEGIN INCLUDED TEXT-------------------- Cisco Security Advisory Cisco Adaptive Security Appliance BGP Bidirectional Forwarding Detection ACL Bypass Vulnerability Medium Advisory ID: cisco-sa-20170315-asa First Published: 2017 March 15 16:00 GMT Version 1.0: Final Workarounds: Yes Cisco Bug IDs: CSCvc68229 CVE-2017-3867 CWE-264 CVSS Score: Base 5.8, Temporal 5.8 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:X/RL:X/RC:X Summary A vulnerability in the Border Gateway Protocol (BGP) Bidirectional Forwarding Detection (BFD) implementation of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to bypass the access control list (ACL) for specific TCP and UDP traffic. The vulnerability occurs because the BFD implementation incorrectly allows traffic with destination ports 3784 and 3785 through the interface ACLs. An attacker could exploit this vulnerability by sending TCP or UDP packets with a destination port of 3784 or 3785 through the ASA. Workarounds that address this vulnerability are available. This advisory is available at the following link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170315-asa Affected Products Vulnerable Products This vulnerability affects Cisco ASA Software. For information about affected software releases, consult the Cisco bug ID(s) at the top of this advisory. Products Confirmed Not Vulnerable No other Cisco products are currently known to be affected by this vulnerability. Workarounds Administrators may consider explicitly blocking TCP and UDP for ports 3784 and 3785 on the ingress ACL for the appropriate interfaces. Fixed Software For information about fixed software releases, consult the Cisco bug ID(s) at the top of this advisory. When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page, to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers. Exploitation and Public Announcements 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. Cisco Security Vulnerability Policy 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. URL https://tools.cisco.com/security/center/content/CiscoSecurityAdvisorycisco-sa-20170315-asa Revision History Version Description Section Status Date 1.0 Initial public release. Final 2017-March-15 Legal Disclaimer 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 standalone 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. Cisco Security Vulnerability Policy 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. - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). 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