CVE-2026-50248

In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, when an auth/rpz zone has a configured primary hostname that resolves to BOGUS A/AAAA, it is still considered as a possible XFR endpoint. A malicious actor that can spoof the hostname's A/AAAA record (no valid RRSIG required) becomes the zone's XFR primary and can replaces the entire zone/the resolver's entire response policy.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-50248.txt	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*

History

24 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) En NLnet Labs Unbound 1.7.0 hasta e incluyendo 1.25.1, cuando una zona auth/rpz tiene un nombre de host primario configurado que resuelve a A/AAAA BOGUS, todavía se considera como un posible punto final XFR. Un actor malicioso que puede suplantar el registro A/AAAA del nombre de host (no se requiere RRSIG válido) se convierte en el primario XFR de la zona y puede reemplazar la zona completa/la política de respuesta completa del resolvedor.

Information

Published : 2026-07-22 14:17

Updated : 2026-10-24 13:10

NVD link : CVE-2026-50248

Mitre link : CVE-2026-50248

CVE.ORG link : CVE-2026-50248

JSON object : View

Products Affected

nlnetlabs

unbound

CWE

CWE-345

Insufficient Verification of Data Authenticity

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