CVE-2022-30698
unbound: novel ghost domain attack that allows attackers to trigger continued resolvability of malicious domain names
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · August 1, 2022
Updated · November 21, 2025
Description
A flaw was found in Unbound, which is vulnerable to a novel type of "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 the expiry of the delegation information by querying Unbound for a second-level subdomain in 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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.5CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CWE-613 · Insufficient Session Expiration