---
title: "CVE-2016-8652\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-2016-8652?format=md
keywords: index, follow
---

# CVE-2016-8652

Publication date 17 February 2017

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**5.9 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2016-8652?format=md#impact-score)

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## Description

The auth component in Dovecot before 2.2.27, when auth-policy is
configured, allows a remote attackers to cause a denial of service (crash)
by aborting authentication without setting a username.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2016-8652?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| dovecot | 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |
| 12.04 LTS precise | 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)

## Notes

---

### [seth-arnold](https://launchpad.net/~seth-arnold)

"Affected version(s): 2.2.25.1 up to 2.2.26.1"

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.9 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.9 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-8652)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-8652)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-8652)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-8652)

### Other references

* <https://marc.info/?l=oss-security&m=148068544322334&w=2>
* <https://www.cve.org/CVERecord?id=CVE-2016-8652>