CVE-2015-5986: An incorrect boundary check can trigger a REQUIRE assertion failure in openpgpkey_61.c

[Michael McNally]

CVE:                       CVE-2015-5986
Document Version:          2.0
Posting date:              02 September 2015
Program Impacted:          BIND
Versions affected:         9.9.7 -> 9.9.7-P2, 9.10.2 -> 9.10.2-P3.
Severity:                  Critical
Exploitable:               Remotely

Description:

   An incorrect boundary check in openpgpkey_61.c can cause named
   to terminate due to a REQUIRE assertion failure.  This defect
   can be deliberately exploited by an attacker who can provide a
   maliciously constructed response in answer to a query.

Impact:

   A server which encounters this error will terminate due to a
   REQUIRE assertion failure, resulting in denial of service to
   clients.

   Recursive servers are at greatest risk from this defect but some
   circumstances may exist in which the attack can be successfully
   exploited against an authoritative server.  Servers should be
   upgraded to a fixed version.

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:

   No workarounds are known to exist.

Active exploits:

   None known.

Solution:

   Upgrade to the patched release most closely related to your
   current version of BIND. These can all be downloaded from
   http://www.isc.org/downloads.

   +  BIND 9 version 9.9.7-P3
   +  BIND 9 version 9.10.2-P4

   BIND development releases scheduled to be published at the same
   time as the public disclosure of this vulnerability will also
   contain the fix for this security issue.

   +  BIND 9 version 9.9.8rc1
   +  BIND 9 version 9.10.3rc1

Document Revision History:

   1.0 Advance Notification 19 August, 2015
   2.0 Public Disclosure  2 September, 2015

Related Documents:

   See our BIND9 Security Vulnerability Matrix at
   https://kb.isc.org/article/AA-00913 for a complete listing of
   Security Vulnerabilities and versions affected.

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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-01291 is
the complete and official security advisory document.

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