NLnet Labs Unbound fixes 5 vulnerabilities

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[TLP:CLEAR] NLnet Labs Unbound fixes 5 vulnerabilities

In version 1.26.2 [1] of Unbound, NLnet Labs fixes 5 vulnerabilities [2][3][4][5][6]. The most severe vulnerability is described below; the remaining ones can be found at [3][4][5][6].

NLnet Labs Unbound - DoS (CVE-2026-97206)

CVSS 7.5 (High)

An unauthenticated remote attacker with a DNS-over-QUIC (DoQ) client can perform a DoS attack via QUIC path migration when running in multi-threaded mode [1][2].

The vulnerability is present in product:

NLnetLabs Unbound; >=1.22.0, <1.26.2;

CVSS: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

More information:

CVE-2026-97206 at cve.org, NVD
CWE-416: Use After Free at cwe.mitre.org

The vulnerability was publicly disclosed 21. 10. 2026.

Links

By CESNET, z.s.p.o. Martin Krajči on 27. 10. 2026.

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[TLP:CLEAR] NLnet Labs Unbound fixes 5 vulnerabilities

NLnet Labs Unbound - DoS (CVE-2026-97206)

CVSS 7.5 (High)

Links