23 December 2015
Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2015.3213 CVE-2015-8373 - ISC Kea: unexpected termination while handling a malformed packet 23 December 2015 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: ISC Kea Publisher: ISC Operating System: UNIX variants (UNIX, Linux, OSX) Impact/Access: Denial of Service -- Remote/Unauthenticated Resolution: Patch/Upgrade CVE Names: CVE-2015-8373 Original Bulletin: https://kb.isc.org/article/AA-01318 - --------------------------BEGIN INCLUDED TEXT-------------------- CVE-2015-8373 - ISC Kea: unexpected termination while handling a malformed packet Author: ISC Support Reference Number: AA-01318 Views: 234 Created: 2015-11-30 17:17 Last Updated: 2015-12-22 22:16 0 Rating/ Voters ISC Kea may terminate unexpectedly (crash) while handling a malformed client packet. CVE: CVE-2015-8373 Document Version: 2.0 Posting date: 22 December 2015 Program Impacted: ISC Kea Versions affected: 0.9.2, 1.0.0-beta Severity: Critical Exploitable: Remotely Description: Related defects in the kea-dhcp4 and kea-dhcp6 servers can cause the server to crash during option processing if a client sends a malformed packet. The kea-dhcp4 server is vulnerable only in versions 0.9.2 and 1.0.0-beta, and furthermore only when logging at debug level 40 or higher. Servers running kea-dhcp4 versions 0.9.1 or lower, and servers which are not logging or are logging at debug level 39 or below are not vulnerable. The kea-dhcp6 server is vulnerable only in versions 0.9.2 and 1.0.0-beta, and furthermore only when logging at debug level 45 or higher. Servers running kea-dhcp6 versions 0.9.1 or lower, and servers which are not logging or are logging at debug level 44 or below are not vulnerable. Impact: An attacker sending a crafted malformed packet can cause an ISC Kea server providing DHCP services to IPv4 or IPv6 clients to exit unexpectedly. CVSS Score: 7.1 CVSS Vector: (AV:N/AC:M/Au:N/C:N/I:N/A:C) For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=(AV:N/AC:M/Au:N/C:N/I:N/A:C) Workarounds: For DHCPv4 services, disabling debug logging or logging at debug levels of 39 or lower will protect ISC Kea against this vulnerability. For DHCPv6 services, disabling debug logging or logging at debug levels of 44 or lower will protect ISC Kea against this vulnerability. Active exploits: No known active exploits exist; this vulnerability was found during internal testing. Solution: Upgrade to the patched release most closely related to your current version of ISC Kea. These can all be downloaded from http://www.isc.org/downloads. ISC Kea version 0.9.2-P1 ISC Kea version 1.0.0-beta2 Document Revision History: 1.0 Advance Notification 15 December 2015 1.1 Revised 18 December 2015 (limiting vulnerable versions to 0.9.2 and 1.0.0-beta) 1.2 Revised 21 December 2015 (DHCPv4 workarounds determined and added) 2.0 Public Disclosure, 22 December 2015 Related Documents: If you'd like more information on ISC Subscription Support and Advance Security Notifications, please visit http://www.isc.org/support/. Do you still have questions? Questions regarding this advisory should go to firstname.lastname@example.org. To report a new issue, please encrypt your message using email@example.com's PGP key which can be found here: https://www.isc.org/downloads/software-support-policy/openpgp-key/. If you are unable to use encrypted email, you may also report new issues at: https://www.isc.org/community/report-bug/. Note: ISC patches only currently supported versions. When possible we indicate EOL versions affected. (For current information on which versions are actively supported, please see http://www.isc.org/downloads/). ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here: https://kb.isc.org/article/AA-00861/164/ISC-Software-Defect-and-Security-Vulnerability-Disclosure-Policy.html This Knowledge Base article https://kb.isc.org/article/AA-01318 is the complete and official security advisory document. Legal Disclaimer: Internet Systems Consortium (ISC) is providing this notice on an "AS IS" basis. No warranty or guarantee of any kind is expressed in this notice and none should be implied. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any implied warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. 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