-------- Original Message -------- Subject: ISC Security Advisory: Handling of zero length rdata can cause named to terminate,unexpectedly Date: Mon, 04 Jun 2012 05:25:50 -0700 From: Larissa Shapiro To: bind-announce@lists.isc.org ISC Security Advisory: Note: This email advisory is provided for your information. The most up to date advisory information will always be at: http://www.isc.org/software/bind/advisories/cve-2012-1667 please use this URL for the most up to date advisory information. Title: 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. CVE: CVE-2012-1667 Document Version: 1.0 Posting date: 4 June 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 Severity: Critical Exploitable: Remotely Description: 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. Impact: 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. Solution: Upgrade to one of the following versions: https://www.isc.org/software/bind/96-esv-r7-p1 https://www.isc.org/software/bind/976-p1 https://www.isc.org/software/bind/983-p1 https://www.isc.org/software/bind/991-p1 Exploit Status: No known active exploits but a public discussion of the issue has taken place on a public mailing list. 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 References: - Do you have questions? Questions regarding this advisory should go to security-officer@isc.org. - ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here: https://www.isc.org/security-vulnerability-disclosure-policy See our BIND Security Matrix for a complete listing of Security Vulnerabilites and versions affected. Note: ISC patches only Currently supported versions. When possible we indicate EOL versions affected. Legal Disclaimer: 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 inferred. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any inferred warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. Your use of, 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 distribution URL in the following section is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors. -- =========================== Larissa Shapiro BIND and DHCP Product Manager, Internet Systems Consortium larissas@isc.org +1 650 423 1335 http://www.isc.org Need BIND or DHCP support? Look to the experts!