---
title: "CVE-2018-5735\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-2018-5735?format=md
keywords: index, follow
---

# CVE-2018-5735

Publication date 16 February 2018

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2018-5735?format=md#impact-score)

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## Description

The Debian backport of the fix for CVE-2017-3137 leads to assertion failure
in validator.c:1858; Affects Debian versions 9.9.5.dfsg-9+deb8u15;
9.9.5.dfsg-9+deb8u18; 9.10.3.dfsg.P4-12.3+deb9u5; 9.11.5.P4+dfsg-5.1 No ISC
releases are affected. Other packages from other distributions who did
similar backports for the fix for 2017-3137 may also be affected.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| bind9 | 17.10 artful | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |

---

* [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-2018-5735?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 |
| --- | --- |
| bind9 | * Upstream:   <https://source.isc.org/cgi-bin/gitweb.cgi/?p=bind9.git;a=commit;h=07dbb507d2913fc35c7edbe3692a976e3248a911> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-5735)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-5735)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-5735)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2018-5735)

### Related Ubuntu Security Notices (USN)

+ [USN-3574-1](https://usn.ubuntu.com/USN-3574-1)
+ Bind vulnerability
+ 19 February 2018

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2018-5735>