---
title: "CVE-2018-5732\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-2018-5732?format=md
keywords: index, follow
---

# CVE-2018-5732

Publication date 1 March 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-2018-5732?format=md#impact-score)

Toggle side navigation

## Description

Failure to properly bounds-check a buffer used for processing DHCP options
allows a malicious server (or an entity masquerading as a server) to cause
a buffer overflow (and resulting crash) in dhclient by sending a response
containing a specially constructed options section. Affects ISC DHCP
versions 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| isc-dhcp | 18.04 LTS bionic | Fixed 4.3.5-3ubuntu5 |
| 17.10 artful | Fixed 4.3.5-3ubuntu2.2 |
| 16.04 LTS xenial | Fixed 4.3.3-5ubuntu12.9 |
| 14.04 LTS trusty | Fixed 4.2.4-7ubuntu12.12 |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## 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-2018-5732)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-5732)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-5732)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2018-5732)

### Related Ubuntu Security Notices (USN)

+ [USN-3586-1](https://usn.ubuntu.com/USN-3586-1)
+ DHCP vulnerabilities
+ 1 March 2018

+ [USN-3586-2](https://usn.ubuntu.com/USN-3586-2)
+ DHCP vulnerabilities
+ 28 May 2018

### Other references

* <https://kb.isc.org/article/AA-01565/75/CVE-2018-5732>
* <https://www.cve.org/CVERecord?id=CVE-2018-5732>