title: A packet containing a malformed DUID can cause the kea-dhcp6 server to terminate
description: A missing check on incoming client requests can be exploited to cause a situation where the Kea server's lease storage contains leases which are rejected as invalid when the server tries to load leases from storage on restart. If the number of such leases exceeds a hard-coded limit in the Kea code, a server trying to restart will conclude that there is a problem with its lease store and give up. Versions affected: 1.4.0 to 1.5.0, 1.6.0-beta1, and 1.6.0-beta2
problem types: Only Kea servers which use memfile storage for leases are affected by this vulnerability.  An attacker can exploit the missing check to deliberately create a situation where the server will not restart properly should it stop for any reason.
affected:
{
product: Kea
vendor: ISC
versions:
status: affected, version: 1.4.0 to 1.5.0
status: affected, version: 1.6.0-beta1
status: affected, version: 1.6.0-beta2
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 5.7
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
version: 3.1
]
solutions: Upgrade to a version of Kea containing a fix, available via
https://www.isc.org/downloads.
-  Kea 1.4.0-P2
-  Kea 1.5.0-P1
-  Kea 1.6.0