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

AA-01161

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

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

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 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/.

Do you still have questions?  Questions regarding this advisory should go to security-officer@isc.orgTo report a new issue, please encrypt your message using security-officer@isc.org'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/mission/contact/.

Note: ISC patches only currently supported versions. 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: ISC Software Defect and Security Vulnerability Disclosure Policy

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

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