CVE-2026-55708
Description
A flaw in Unbound's unbound-control utility can omit default-protected zones when initializing local data for a view. This allows queries for protected local names to bypass intended policies and leak to the public DNS, potentially exposing sensitive network information.
Statement
This is a Low impact flaw in Unbound. A highly privileged user, by using unbound-control to create a view without initial local data, can cause queries for internal network names to be sent to public DNS servers. This bypasses local policy and could lead to the disclosure of internal network information.
Mitigation
Do not run unbound-control view_local_data / view_local_datas on named views that started with no local-data; put local-data (or the RFC 1918 / AS112 / .onion / .localhost local-zones) in unbound.conf so the tree is built at startup with the defaults. If views or remote control are unused, leave control-enable: no and keep the control socket admin-only. Block Unbound from sending those names to the public Internet.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 3.1 | N/A | 3.1 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | High | N/A | High |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Frequently Asked Questions
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