If a DHCPv4 client sends a request with some specific options, and Kea fails to find an appropriate subnet for the client, the kea-dhcp4 process will abort with an assertion failure. This happens only if the client request is unicast directly to Kea; broadcast messages do not cause the problem.
This issue affects Kea versions 2.7.1 through 2.7.9, 3.0.0, and 3.1.0.
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.