Cisco Security Advisory
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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
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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://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170315-asa
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Administrators may consider explicitly blocking TCP and UDP for ports 3784 and 3785 on the ingress ACL for the appropriate interfaces.
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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.
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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.
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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.
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Show LessVersion Description Section Status Date 1.0 Initial public release. — Final 2017-March-15
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