CVE-2022-30698

Novel "ghost domain names" attack by introducing subdomain delegations

Published Aug 1, 2022 CVSS 3.1 · 6.5 Medium EPSS 1.2% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-3371-1 unbound security update
EUVD EUVD EUVD-2022-52528 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.
Ubuntu USN Ubuntu USN USN-5569-1 Unbound vulnerabilities
History
Type Values Removed Values Added
Metrics epss

{'score': 0.00085}

epss

{'score': 0.00093}

Weaknesses

Sources

Status
PUBLISHED
Assigner
NLnet Labs
Published
Updated
Sep 16, 2024, 7:35 PM
Reserved
May 13, 2022, 12:00 AM
Status
Modified
Published
Aug 1, 2022, 3:15 PM
Modified
Jun 17, 2026, 4:44 AM
Severity
Moderate
Public date
Aug 1, 2022, 12:00 AM