CVE-2012-1667: Handling of zero length rdata can cause named to terminate unexpectedly
Processing of DNS resource records where the rdata field is zero length may cause various issues for the servers handling them.
Document version: 1.4
Posting date: 04 Jun 2012
Program impacted: BIND
Versions affected: 9.0.x -> 9.6.x, 9.4-ESV->9.4-ESV-R5-P1, 9.6-ESV->9.6-ESV-R7, 9.7.0->9.7.6, 9.8.0->9.8.3, 9.9.0->9.9.1
This problem was uncovered while testing with experimental DNS record types. It is possible to add records to BIND with null (zero length) rdata fields.
Processing of these records may lead to unexpected outcomes. Recursive servers may crash or disclose some portion of memory to the client. Secondary servers may crash on restart after transferring a zone containing these records. Master servers may corrupt zone data if the zone option "auto-dnssec" is set to "maintain". Other unexpected problems that are not listed here may also be encountered.
This issue primarily affects recursive nameservers. Authoritative nameservers will only be impacted if an administrator configures experimental record types with no data. If the server is configured this way, then secondaries can crash on restart after transferring that zone. Zone data on the master can become corrupted if the zone with those records has named configured to manage the DNSSEC key rotation.
CVSS Score: 8.5
CVSS Equation: (AV:N/AC:L/Au:N/C:P/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:P/I:N/A:C).
Workarounds: Workarounds are under investigation, but none are known at this time.
Active exploits: No known active exploits but a public discussion of the issue has taken place on a public mailing list.
Solution: Upgrade to BIND version 9.6-ESV-R7-P1, 9.7.6-P1, 9.8.3-P1, or 9.9.1-P1
Acknowledgment: Dan Luther, Level3 Communications, for finding the issue, Jeffrey A. Spain,
Cincinnati Day School, for replication and testing.
Document Revision History:
1.0 Released to Public 4 June, 2012
1.1 Updated Severity to Critical
1.2 Added German Translation 7 June, 2012
1.3 Added link to FAQ supplemental article in KB
1.4 Added Chinese Translation
- German Translation: http://cert.uni-stuttgart.de/ticker/article.php?mid=1694
- Chinese Translation: no longer available
If you'd like more information on ISC Subscription Support and Advance Security Notifications, please visit https://www.isc.org/support/.
See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.
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 https://www.isc.org/downloads/.)
ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy.
This Knowledgebase article 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.