9.0.x -> 9.8.x, 9.9.0->9.9.9-P2, 9.9.3-S1->9.9.9-S3, 9.10.0->9.10.4-P2,
Testing by ISC has uncovered a critical error condition which can occur when a nameserver is constructing a response. A defect in the rendering of messages into packets can cause named to exit with an assertion failure in buffer.c while constructing a response to a query that meets certain criteria.
This assertion can be triggered even if the apparent source address isn't allowed to make queries (i.e. doesn't match 'allow-query').
All servers are vulnerable if they can receive request packets from any source.
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&adv&version=2&vector=(AV:N/AC:L/Au:N/C:N/I:N/A:C)
No practical workarounds exist.
A step-by-step breakdown of the issue has been published and working Metasploit code is available. Crashes have been reported that appear to be the result active exploitation.
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 9.9.9-P3
- BIND 9 version 9.10.4-P3
- BIND 9 version 9.11.0rc3
BIND 9 Supported Preview edition is a feature preview version of BIND provided exclusively to eligible ISC Support customers.
Document Revision History:
1.0 2016-09-14 - Advance Notification
1.1 2016-09-21 - Added information about the Stable Preview release to versions affected. Updated solution section to reflect replacing 9.11.0rc2 with 9.11.0rc3 and 9.9.9-S4 with 9.9.9-S5.
2.0 2016-09-27 - Posting date changed and public disclosure.
2.1 2016-10-04 - Updated 'Active exploits' section.
See our BIND9 Security Vulnerability Matrix at 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 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 email@example.com. To report a new issue, please encrypt your message using firstname.lastname@example.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/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-01419 is the complete and official security advisory document.
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. Your use or reliance on this notice or materials referred to in this notice is at your own risk. ISC may change this notice at any time. A stand-alone copy or paraphrase of the text of this document that omits the document URL is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors.
© 2001-2017 Internet Systems ConsortiumFor assistance with problems and questions for which you have not been able to find an answer in our Knowledge Base, we recommend searching our community mailing list archives and/or posting your question there (you will need to register there first for your posts to be accepted). The bind-users and the dhcp-users lists particularly have a long-standing and active membership.ISC relies on the financial support of the community to fund the development of its open source software products. If you would like to support future product evolution and maintenance as well having peace of mind knowing that our team of experts are poised to provide you with individual technical assistance whenever you call upon them, then please consider our Professional Subscription Support services - details can be found on our main website.