A denial of service vulnerability was discovered in nbdkit. A client issuing a certain sequence of commands could possibly trigger an assertion failure, causing nbdkit to exit. This issue only affected nbdkit versions 1.12.7, 1.14.1, and 1.15.1.
If nbdkit is configured with TLS client authentication, only trusted clients can carry out this attack.
Only attackers that can connect to the nbdkit service can exploit this vulnerability. If nbdkit is not exposed over TCP (eg, nbdkit -U), or is bound only to a private network interface, or is protected by firewall rules, the attack surface is correspondingly limited.