title: named may terminate unexpectedly when processing ECS options in repeated responses to iterative queries
description: Processing of repeated responses to the same query, where both responses contain ECS pseudo-options, but where the first is broken in some way, can cause BIND to exit with an assertion failure.
'Broken' in this context is anything that would cause the resolver to reject the query response, such as a mismatch between query and answer name.
This issue affects BIND 9 versions 9.11.4-S1 through 9.11.37-S1 and 9.16.8-S1 through 9.16.36-S1.
affected:
{
vendor: ISC
product: BIND 9
versions:
version: 9.11.4-S1, lessThanOrEqual: 9.11.37-S1, status: affected, versionType: custom
version: 9.16.8-S1, lessThanOrEqual: 9.16.36-S1, status: affected, versionType: custom
defaultStatus: unaffected
}
metrics:
cvssV3_1: [
version: 3.1
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: NONE
integrityImpact: NONE
availabilityImpact: HIGH
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
baseScore: 7.5
baseSeverity: HIGH
]
exploits: We are not aware of any active exploits.
solutions: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.37-S1.
workarounds: No workarounds known.