Red Hat Bugzilla – Bug 1315690
CVE-2016-2088 bind: malformed packet containing multiple cookie options can trigger assertion failure
Last modified: 2016-03-15 08:37:30 EDT
The following flaw, reported by ISC, was found in BIND 9.10:
BIND 9.10 has preliminary support for DNS cookies (or source identity tokens), a proposed mechanism designed to allow lightweight transaction security between a querying party and a nameserver. An error in the BIND code implementing support for this optional feature permits a deliberately misconstructed packet containing multiple cookie options to cause named to terminate with an INSIST assertion failure in resolver.c if DNS cookie support is enabled in the server. Only servers with DNS cookie support enabled at build time can be affected by this defect; in servers which do not have DNS cookie support selected any cookies encountered will be ignored as unknown option types.
Servers which are built with DNS cookie support enabled are vulnerable to denial of service if an attacker can cause them to receive and process a response that contains multiple cookie options.
Created bind tracking bugs for this issue:
Affects: fedora-all [bug 1316445]
This issue did not affect the versions of bind97 as shipped with Red Hat Enterprise Linux 5 and bind as shipped with Red Hat Enterprise Linux 5, 6, and 7 as they did not include support for DNS cookies.