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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2016.3031 Cisco ASR 5000 Series IPv6 Packet Processing Denial of Service Vulnerability 20 December 2016 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Cisco ASR 5000 Publisher: Cisco Systems Operating System: Cisco Impact/Access: Denial of Service -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2016-6467 Original Bulletin: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161207-asr - --------------------------BEGIN INCLUDED TEXT-------------------- Cisco Security Advisory Cisco ASR 5000 Series IPv6 Packet Processing Denial of Service Vulnerability Medium Advisory ID: cisco-sa-20161207-asr First Published: 2016 December 7 16:00 GMT Version 1.0: Final Workarounds: No workarounds available Cisco Bug IDs: CSCva84552 CVSS Score: Base 5.0, Temporal 4.1 CVE-2016-6467 CWE-399 Summary A vulnerability in IPv6 packet fragment reassembly of StarOS for Cisco Aggregation Services Router (ASR) 5000 Series Switch could allow an unauthenticated, remote attacker to cause an unexpected reload of the Network Processing Unit (NPU) process. The vulnerability is due to lack of proper input validation of the IPv6 fragment lengths. An attacker could exploit this vulnerability by sending a crafted IPv6 fragment chain to the targeted device. An exploit could allow the attacker to cause a denial of service (DoS) condition if the NPU process unexpectedly reloads. The DoS condition could temporarily impact user traffic. There are no workarounds that address this vulnerability. This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161207-asr Affected Products Vulnerable Products This vulnerability affects Cisco Aggregation Services Router (ASR) 5000. 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. Indicators of Compromise The ASR5K will write out a core file for the NPU process. This file can be viewed by using the following CLI command: # show crash <#> === ==================== ======== ========== =============== ======================= # Time Process Card/CPU/ SW HW_SER_NUM PID VERSION MIO / Crash Card === ==================== ======== ========== =============== ======================= 1 2010-Feb-16+07:56:37 npu 05/0/15340 19.0.M0.61045 ####################### Contact the Cisco Technical Assistance Center (TAC) to review the core file and determine whether the device has been compromised by exploitation of this vulnerability. Workarounds There are no workarounds that address this vulnerability. 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 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. URL http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161207-asr Revision History Version Description Section Status Date 1.0 Initial public release. — Final 2016-December-07 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. - --------------------------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. 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On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBWFjJOIx+lLeg9Ub1AQiMeRAAhpVuSa11Wj961uMfg17LkWg9oiAIoP/z 8fxzbGiZ58JkRHcCj60u8QiqY3KY1J1ZgnsGdrc8vlCRFbS9bGfUDDWOm+FqX0bJ ATKE8+lcTM6rfrJKOglyHOppgiBgrD9AlpGLjK/e+titarqQ3xeqRGj2SJLQoZhy I0Q6pqRUgtH1AWxX0v2WeNG44umFYkUGlpIPc7YL9UAS0QNTZPPvW00Sna1lHCtP HgTnw93pLOryN3JWZktCn7SfIPpaNq8bGXALc2hb6TfyaXkQGmvAjl6p8boz0jeC lFNV3RtuRXm+btaH70lNwQhAKvm3YkHt3UK/rnZ4V3mu+Nz4k8pFjVokxZZofbBj k+7niyp3eH/el9Bw5bDeS4QuAiS1vzzyt19UDdwcfPd4WuPxQKM1BxUePsoHYzFb y1DsJ9Q+1aFSjhTiga6i88xxJJY71VsWvH+aiK8JqITMBKGGnzbZ5d8QvdXnnSvo FqU9jxrpbnReYGMmuypE0F2P64vJWrePoWPF4ybURabFoKd1puhTcjBjxv98pIbU EZM9CFv6FV5ge8eGHaJvJO6SQjpDPMTHRcb0VCru9Pudzzb9o+Cp+TgM0DEacOUi GcBiePVKnSWe1HbSoY5RnkrNDT/5cJZ+9/cr32VsLCjgD+S9EePRQpAyQm2HahnG NkgsJyisXMg= =ozyY -----END PGP SIGNATURE-----