title: BIND Supported Preview Edition can exit with an assertion failure if nxdomain-redirect is used
description: In BIND Supported Preview Edition, an error in the nxdomain-redirect feature can occur in versions which support EDNS Client Subnet (ECS) features. In those versions which have ECS support, enabling nxdomain-redirect is likely to lead to BIND exiting due to assertion failure. Versions affected: BIND Supported Preview Edition version 9.10.5-S1 -> 9.11.5-S5. ONLY BIND Supported Preview Edition releases are affected.
problem types: If nxdomain-redirect is enabled (via configuration) in a vulnerable BIND release, a malicious party can cause BIND to exit by deliberately triggering the bug.
affected:
{
product: BIND 9 Supported Preview Edition
vendor: ISC
versions:
status: affected, version: BIND 9 9.10.5-S1 -> 9.11.5-S5
}
metrics:
cvssV3_0: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 5.3
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
version: 3.0
]
solutions: Upgrade to the patched release most closely related to your current version of BIND:
BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.
+    BIND 9.11.5-S6
+    BIND 9.11.6-S1
workarounds: Exploitation of this defect can be effectively prevented by disabling the nxdomain-redirect feature in the nameserver's configuration.