CVE-2026-14586 (Medium) detected in multiple libraries

[mend-bolt-for-github]

CVE-2026-14586 - Medium Severity Vulnerability

Vulnerable Libraries - src4.0.4, src4.0.4, src4.0.4, src4.0.4

src4.0.4

Library home page: https://github.com/MidnightBSD/src.git

Vulnerable Source Files (4)

/contrib/unbound/util/netevent.c
/contrib/unbound/util/netevent.h
/contrib/unbound/services/listen_dnsport.h
/contrib/unbound/services/listen_dnsport.c

src4.0.4

Library home page: https://github.com/MidnightBSD/src.git

Vulnerable Source Files (4)

/contrib/unbound/util/netevent.c
/contrib/unbound/util/netevent.h
/contrib/unbound/services/listen_dnsport.h
/contrib/unbound/services/listen_dnsport.c

src4.0.4

Library home page: https://github.com/MidnightBSD/src.git

Vulnerable Source Files (4)

/contrib/unbound/util/netevent.c
/contrib/unbound/util/netevent.h
/contrib/unbound/services/listen_dnsport.h
/contrib/unbound/services/listen_dnsport.c

src4.0.4

Library home page: https://github.com/MidnightBSD/src.git

Vulnerable Source Files (4)

/contrib/unbound/util/netevent.c
/contrib/unbound/util/netevent.h
/contrib/unbound/services/listen_dnsport.h
/contrib/unbound/services/listen_dnsport.c

Found in HEAD commit: 816463d989cc5839c1cca2efb5bf2503408507fb

Found in base branches: stable/4.0, master

Vulnerability Details

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.

Publish Date: 2026-07-22

URL: CVE-2026-14586

CVSS 3 Score Details (5.9)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: High
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: None
  • Integrity Impact: None
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2026-07-22

Fix Resolution: https://github.com/NLnetLabs/unbound.git - release-1.25.2

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