---
title: "CVE-2018-16860\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-2018-16860?format=md
keywords: index, follow
---

# CVE-2018-16860

Publication date 14 May 2019

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-2018-16860?format=md#impact-score)

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## Description

A flaw was found in samba's Heimdal KDC implementation, versions 4.8.x up
to, excluding 4.8.12, 4.9.x up to, excluding 4.9.8 and 4.10.x up to,
excluding 4.10.3, when used in AD DC mode. A man in the middle attacker
could use this flaw to intercept the request to the KDC and replace the
user name (principal) in the request with any desired user name (principal)
that exists in the KDC effectively obtaining a ticket for that principal.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| heimdal | 22.10 kinetic | Not affected |
| 22.04 LTS jammy | Not affected |
| 21.10 impish | Not affected |
| 21.04 hirsute | Not affected |
| 20.10 groovy | Not affected |
| 20.04 LTS focal | Not affected |
| 19.10 eoan | Not affected |
| 19.04 disco | Ignored end of life |
| 18.10 cosmic | Ignored end of life |
| 18.04 LTS bionic | Fixed 7.5.0+dfsg-1ubuntu0.1 |
| 16.04 LTS xenial | Fixed 1.7~git20150920+dfsg-4ubuntu1.16.04.1+esm1  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 1.6~git20131207+dfsg-1ubuntu1.2+esm1  Ubuntu Pro |
| samba | 22.10 kinetic | Fixed 2:4.10.0+dfsg-0ubuntu2.1 |
| 22.04 LTS jammy | Fixed 2:4.10.0+dfsg-0ubuntu2.1 |
| 20.04 LTS focal | Fixed 2:4.10.0+dfsg-0ubuntu2.1 |
| 19.04 disco | Fixed 2:4.10.0+dfsg-0ubuntu2.1 |
| 18.10 cosmic | Fixed 2:4.8.4+dfsg-2ubuntu2.4 |
| 18.04 LTS bionic | Fixed 2:4.7.6+dfsg~ubuntu-0ubuntu2.10 |
| 16.04 LTS xenial | Fixed 2:4.3.11+dfsg-0ubuntu0.16.04.20 |
| 14.04 LTS trusty | Fixed 2:4.3.11+dfsg-0ubuntu0.14.04.20+esm1  Ubuntu Pro |

---

* [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-2018-16860?format=md#patch-details)

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### 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 |
| --- | --- |
| heimdal | * Upstream:   [c6257cc](https://github.com/heimdal/heimdal/commit/c6257cc2c842c0faaeb4ef34e33890ee88c4cbba) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

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

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

**Vector:** CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-16860)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-16860)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-16860)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2018-16860)

### Related Ubuntu Security Notices (USN)

+ [USN-3976-1](https://usn.ubuntu.com/USN-3976-1)
+ Samba vulnerability
+ 14 May 2019

+ [USN-3976-2](https://usn.ubuntu.com/USN-3976-2)
+ Samba vulnerability
+ 14 May 2019

+ [USN-5675-1](https://usn.ubuntu.com/USN-5675-1)
+ Heimdal vulnerabilities
+ 13 October 2022

### Other references

* <https://www.samba.org/samba/security/CVE-2018-16860.html>
* <https://www.cve.org/CVERecord?id=CVE-2018-16860>