CVE-2026-97206 (GCVE-0-2026-97206)

Vulnerability from cvelistv5 – Published: 2026-10-21 08:57 – Updated: 2026-10-21 08:57
VLAI
Title
DNS-over-QUIC (DoQ) path-migration can lead to use-after-free on multi-threaded deployments.
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
NLnet Labs CNA
CNA scorecard B 82/100 over 66 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NLnet Labs Unbound Affected: 1.22.0 , < 1.26.2 (semver)
guessed Create a notification for this product.
Date Public
2026-10-21 00:00
Credits
Kunta Chu (Tsinghua University) Jianjun Chen (Tsinghua University)
Show details on NVD website
To clipboard 

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}



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