CVE-2016-1286: A problem parsing resource record signatures for DNAME resource records can lead to an assertion failure in resolver.c or db.c
Document version: 2.0
Posting date: 09 March 2016
Program impacted: BIND
Versions affected: 9.0.0 -> 9.8.8, 9.9.0 -> 9.9.8-P3, 9.9.3-S1 -> 9.9.8-S5, 9.10.0 -> 9.10.3-P3
Description: An error when parsing signature records for DNAME records having specific properties can lead to named exiting due to an assertion failure in resolver.c or db.c.
An attacker able to cause a server to make a query, deliberately chosen to generate a response containing a signature record which would exercise this vulnerability, can cause named to stop execution with an assertion failure, resulting in denial of service to clients. Recursive resolvers are at the highest risk of vulnerability to this attack, but authoritative-only servers may be also be vulnerable if the attacker can control the answers for records requested when the authoritative server is performing service on zones (e.g. a slave server doing SOA queries). Servers may be affected even if they are not performing validation or have DNSSEC disabled entirely, as long as they receive a response containing offending signature records. Disabling DNSSEC does not provide protection against this vulnerability.
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).
Workarounds: None known.
Active exploits: No known active exploits.
Solution: Upgrade to the patched release most closely related to your current version of BIND:
- BIND 9 version 9.9.8-P4
- BIND 9 version 9.10.3-P4
BIND 9 Supported Preview edition is a feature preview version of BIND provided exclusively to eligible ISC Support customers.
- BIND 9 version 9.9.8-S6
Document Revision History:
1.0 Advance Notification. 02 March 2016 1.1 "Versions affected" and "Solution" text expanded to cover BIND 9 Supported Preview Edition; "Versions affected" and "Impact" text expanded to cover all old versions. 07 March 2016 2.0 Public Disclosure. 09 March 2016
Related Documents: See our BIND 9 Security Vulnerability Matrix for a complete listing of Security Vulnerabilities and versions affected.
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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/).
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