CVE-2026-55708

In NLnet Labs Unbound 1.6.0 up to and including 1.25.1, the 'view_local_data' and 'view_local_datas' commands of 'unbound-control' create a bare local zones tree for an already configured named view when the view is configured with no local data to begin with. However, the creation through the control interface omits adding the default-protected zones (e.g., RFC 1918 reverse, AS112 zones, .onion, .localhost). Once the local zone tree exists without the defaults, every query for a default-protected name from a client mapped to that view escapes to the public DNS via the iterator instead of being answered locally, bypassing local policy expectations.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.6 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-55708.txt	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

24 Jul 2026, 14:24

Type	Values Removed	Values Added
First Time		Nlnetlabs Nlnetlabs unbound
CPE		cpe:2.3:a:nlnetlabs:unbound::::::::
References	~~() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-55708.txt -~~	() https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-55708.txt - Vendor Advisory

22 Jul 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-22 14:17

Updated : 2026-07-24 14:24

NVD link : CVE-2026-55708

Mitre link : CVE-2026-55708

CVE.ORG link : CVE-2026-55708

JSON object : View

Products Affected

nlnetlabs

unbound

CWE

CWE-1188

Insecure Default Initialization of Resource

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