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MEDIUM

Novel "ghost domain names" attack by introducing subdomain delegations

Published Aug 1, 2022

Description

NLnet Labs Unbound, up to and including version 1.16.1 is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. From version 1.16.2 on, Unbound checks the validity of parent delegation records before using cached delegation information.

Affected products

Remediation

No remediation recorded yet.

Weaknesses (1)

References (10)

Change history (0)

No recorded changes yet.

Sources

CVE.org / MITRE

Status PUBLISHED
Assigner NLnet Labs
Published Aug 1, 2022
Updated Sep 16, 2024
Reserved May 13, 2022

CISA Vulnrichment

No data

NVD

Status Modified
Modified Jun 17, 2026

Red Hat

Severity Moderate
Public date Aug 1, 2022
Bugzilla 2116725

ENISA EUVD

Assigner NLnet Labs
Published Aug 1, 2022
Updated Sep 16, 2024

GitHub

No data