CVE-2026-97206 — DNS-over-QUIC (DoQ) path-migration can lead to use-after-free on multi-threaded deployments.
NLnet Labs Unbound, 1.22.0 up to and including version 1.26.1, contains a DNS-over-QUIC (DoQ) lifetime bug reachable by a remote DoQ client under multi-threaded operation. A cli…
Published: 2026-10-21 · CVSS: 7.5 · CVSS 3.1
NLnet Labs Unbound, 1.22.0 up to and including version 1.26.1, contains a DNS-over-QUIC (DoQ) lifetime bug reachable by a remote DoQ client under multi-threaded operation. A client-triggered QUIC path migration can enter stream/connection cleanup while a mesh reply still retains a pointer to the DoQ stream. Cleanup frees the DoQ stream and when the pending mesh reply later completes it dereferences a stale pointer leading to a crash.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7