CVE-2014-3214: A Defect in Prefetch Can Cause Recursive Servers to Crash

[Michael McNally]

A defect in the prefetch feature can cause named to crash when
handling some queries.

CVE:                       CVE-2014-3214
Document Version:          2.0
Posting date:              8 May 2014
Program Impacted:          BIND
Versions affected:         9.10.0
Severity:                  High
Exploitable:               Remotely

Description:

   A defect in the pre-fetch feature (which is enabled by default)
   can cause BIND 9.10.0 to terminate with a "REQUIRE" assertion
   failure if it processes queries whose answers have particular
   attributes.  This can be triggered as the result of normal query
   processing.

Impact:

   Recursive nameservers are vulnerable to this defect.  Authoritative-only
   servers are not at risk.  On an affected nameserver, the assertion
   failure, if triggered, results in an immediate exit from named,
   denying service to clients attempting to query the recursive
   server.

CVSS Score:                7.8

CVSS Vector:               (AV:N/AC:L/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&version=2&vector=(AV:N/AC:L/Au:N/C:N/I:N/A:C)

Workarounds:

   The problematic code is bypassed and prefetching is disabled by
   setting the prefetch option to zero within the options block 
   in named.conf:

      prefetch 0;

Active exploits: 

   There are no known active exploits but the crash has been
   independently reported by multiple organizations.

Solution: 

   Upgrade to the patched release listed below.  BIND software can
   be downloaded from http://www.isc.org/downloads

   -  BIND 9 version 9.10.0-P1 

Acknowledgements:

   ISC would like to thank each of the individuals who independently
   discovered and reported the problem.

Document Revision History:

   1.0 Phase One, Advance Notification 7 May 2014
   2.0 Phase Four, Public Disclosure: 8 May 2014

Related Documents:

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

If you'd like more information on ISC product support please visit
http://www.dns-co.com/solutions/.

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should go to security-officer at isc.org.  To report a new issue,
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issues at: https://www.isc.org/mission/contact/.

Note:

   ISC patches only currently supported versions.
   http://www.isc.org/downloads/software-support-policy/bind-software-status/
   When possible we indicate EOL versions affected.

   ISC Security Vulnerability Disclosure Policy:  Details of our
   current security advisory policy and practice can be found here:
   https://kb.isc.org/article/AA-00861/0

   This Knowledge Base article https://kb.isc.org/editArticle/AA-01161
   is the complete and official security advisory document.

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