---
title: "CVE-2022-30698\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2022-30698?format=md
keywords: index, follow
---

# CVE-2022-30698

Publication date 1 August 2022

Last updated 18 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**6.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2022-30698?format=md#impact-score)

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## 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.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| unbound | 26.04 LTS resolute | Fixed 1.16.2-1 |
| 25.10 questing | Fixed 1.16.2-1 |
| 25.04 plucky | Fixed 1.16.2-1 |
| 24.10 oracular | Fixed 1.16.2-1 |
| 24.04 LTS noble | Fixed 1.16.2-1 |
| 23.10 mantic | Fixed 1.16.2-1 |
| 23.04 lunar | Fixed 1.16.2-1 |
| 22.10 kinetic | Fixed 1.16.2-1 |
| 22.04 LTS jammy | Fixed 1.13.1-1ubuntu5.1 |
| 20.04 LTS focal | Fixed 1.9.4-2ubuntu1.3 |
| 18.04 LTS bionic | Fixed 1.6.7-1ubuntu2.5 |
| 16.04 LTS xenial | Vulnerable |
| 14.04 LTS trusty | Vulnerable |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2022-30698?format=md#patch-details)

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| unbound | * Upstream:   [f6753a0](https://github.com/NLnetLabs/unbound/commit/f6753a0f1018133df552347a199e0362fc1dac68) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

6.5 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | None |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 6.5 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-30698)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2022-30698)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2022-30698)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2022-30698)

### Related Ubuntu Security Notices (USN)

+ [USN-5569-1](https://usn.ubuntu.com/USN-5569-1)
+ Unbound vulnerabilities
+ 16 August 2022

### Other references

* <https://www.nlnetlabs.nl/downloads/unbound/CVE-2022-30698_CVE-2022-30699.txt>
* <https://www.cve.org/CVERecord?id=CVE-2022-30698>