DNS-over-QUIC (DoQ) path-migration can lead to use-after-free on multi-threaded deployments. (NLnet Labs Unbound)

CVE-2026-97206
HIGH 7.5

At a glance

Source
NVD
EPSS
EPSS 0.33 % · percentile 27 ()
State
PUBLISHED
Published
Updated
Assigner
NLnet Labs
NVD status
Awaiting Analysis

Description

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.

Weaknesses (CWE)

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNLnet Labs
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · sep@nlnetlabs.nl (Secondary)

European references

Affected products

ProductVersions
NLnet Labs · Unboundaffected 1.22.0 < 1.26.2

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD