CVE-2026-55708
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Last Modified:
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.
Additional information
- This content is not included.Bugzilla 2506131: unbound: Unbound: Information disclosure due to local policy bypass via unbound-control
- Content from cwe.mitre.org is not included.CWE-213: Exposure of Sensitive Information Due to Incompatible Policies
External References
Affected Packages and Issued Red Hat Security Errata
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.
| Products / Services | Components | State | Errata |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | unbound | Fix deferred | |
| Red Hat Enterprise Linux 6 | unbound | Not affected | |
| Red Hat Enterprise Linux 7 | unbound | Fix deferred | |
| Red Hat Enterprise Linux 8 | unbound | Fix deferred | |
| Red Hat Enterprise Linux 9 | unbound | Fix deferred | |
| Red Hat Hardened Images | unbound-main | Fixed | RHSA-2026:43588 |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-8 | Fix deferred | |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-9 | Fix deferred | |
| No matching records found | |||
Common Vulnerability Scoring System (CVSS) Score Details
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 Authorities (CNA) source for its products and services (see Red Hat classifications ).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| CVSS v3 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 Impact | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
CVSS v3 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
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
For more information, see https://access.redhat.com/solutions/762393.
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
- "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
- "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.
What can I do if my product is listed as "Will not fix"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
What can I do if my product is listed as "Fix deferred"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
- Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.
What is a mitigation?
I have a Red Hat product but it is not in the above list, is it affected?
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