CVE-2026-14586 (GCVE-0-2026-14586)

Vulnerability from cvelistv5 – Published: 2026-07-22 13:03 – Updated: 2026-07-22 14:33
VLAI
Title
Assertion in libngtcp2 when under pressure in high concurrency DNS-over-QUIC environments
Summary
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, in DNS-over-QUIC environments, with high concurrency and under pressure, an assertion in libngtcp2 about monotonic timestamps could trigger and result in server termination and thus denial of service. When interfacing with libngtcp2, for DNS-over-QUIC support in Unbound, it is expected to use monotonic time. Unbound was using realtime instead, and in DoQ environments with high concurrency and under pressure, an assert in libngtcp2 for the quic timestamp would trigger and terminate the server.This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 14:32 UTC
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 , < 1.25.2 (semver)
guessed Create a notification for this product.
Date Public
2026-07-22 00:00
Credits
Kunta Chu (Tsinghua University) Kaihua Wang (Tsinghua University) Jianjun Chen (Tsinghua University)
Show details on NVD website
To clipboard 

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