https://lists.isc.org/pipermail/bf-announce/2011-November/000229.html Last night a large number of recursive operators had BIND crashes at the same time. ISC then issued the following public advisory: https://www.isc.org/software/bind/advisories/cve-2011-tbd We are releasing mitigation code to you, our customers, at 8:30am PST, to aid you in managing this issue. In no less than one hour (at or after 9:30am PST) ISC will release mitigation code to the public for this issue. Interim Advisory: *Title:* BIND 9 Resolver crashes after logging an error in query.c *Summary:* Organizations across the Internet reported crashes interrupting service on BIND 9 nameservers performing RECURSIVE queries. Affected servers crashed after logging an error in query.c with the following message: "INSIST(! dns_rdataset_isassociated(sigrdataset))" Multiple versions were reported being affected, including all currently supported release versions of ISC BIND 9. ISC is actively investigating the root cause and has produced patches which prevent the crash. Further information will be made available soon. *Document Version:* 1.1 *Posting date:* 16 November 2011 *Program Impacted:* BIND *Versions affected:* BIND 9.4-ESV-R, BIND 9.6-ESV-R, BIND 9.7, BIND 9.8 *Exploitable:* Remotely *Description:* An as-yet unidentified network event caused BIND 9 resolvers to cache an invalid record, subsequent queries for which could crash the resolvers with an assertion failure. ISC is working on determining the ultimate cause by which a record with this particular inconsistency is cached.At this time we are making available a patch which makes named recover gracefully from the inconsistency, preventing the abnormal exit. The patch has two components. When a client query is handled, the code which processes the response to the client has to ask the cache for the records for the name that is being queried. The first component of the patch prevents the cache from returning the inconsistent data. The second component prevents named from crashing if it detects that it has been given an inconsistent answer of this nature. Severity: High *CVSS Score:* 7.8 *CVSS Equation:* (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 <http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=%28AV:N/AC:L/Au:N/C:N/I:N/A:C>) *Workarounds:* No workarounds are known. The solution is to upgrade. Upgrade BIND to one of the following patched versions: 9.4-ESV-R5-P1 has been published to: ftp://ftp.isc.org/isc/bind9/private/973aa955cb3020fb 9.6-ESV-R5-P1 has been published to: ftp://ftp.isc.org/isc/bind9/private/41eb13f25615ed36 9.7.4-P1 has been published to: ftp://ftp.isc.org/isc/bind9/private/c88862ecdcade50e 9.8.1-P1 has been published to: ftp://ftp.isc.org/isc/bind9/private/afa41f8203d50bed *Solution:* Patches mitigating the issue are available at: *Exploit Status:* ISC is receiving multiple reports and working with multiple customers on this issue. Please E-mail all questions, packet captures, and details to security-officer at isc.org <mailto:security-officer at isc.org> *Acknowledgment:* Simutaneously reported by multiple people in the DNS community. Thank you to everyone who has provided and continues to provide information. *Document Revision History* 1.0 16 November 2011 - Interim Advisory 1.1 16 November 2011 - Mitigation patches, further information *References:* *- Do you have Questions?* Questions regarding this advisory should go to security-officer at isc.org <mailto:security-officer at 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>https://www.isc.org/security-vulnerability-disclosure-policy *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 implied. 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.
*** This bug has been marked as a duplicate of bug 754398 ***