---
title: "CVE-2016-10195\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-2016-10195?format=md
keywords: index, follow
---

# CVE-2016-10195

Publication date 31 December 2016

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2016-10195?format=md#impact-score)

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## Description

The name\_parse function in evdns.c in libevent before 2.1.6-beta allows
remote attackers to have unspecified impact via vectors involving the
label\_len variable, which triggers an out-of-bounds stack read.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| firefox | 17.04 zesty | Fixed 53.0+build6-0ubuntu0.17.04.1 |
| 16.10 yakkety | Fixed 53.0+build6-0ubuntu0.16.10.1 |
| 16.04 LTS xenial | Fixed 53.0+build6-0ubuntu0.16.04.1 |
| 14.04 LTS trusty | Fixed 53.0+build6-0ubuntu0.14.04.1 |
| 12.04 LTS precise | Ignored |
| libevent | 17.04 zesty | Fixed 2.0.21-stable-3 |
| 16.10 yakkety | Fixed 2.0.21-stable-2ubuntu0.16.10.1 |
| 16.04 LTS xenial | Fixed 2.0.21-stable-2ubuntu0.16.04.1 |
| 14.04 LTS trusty | Fixed 2.0.21-stable-1ubuntu1.14.04.2 |
| 12.04 LTS precise | Fixed 2.0.16-stable-1ubuntu0.2 |
| thunderbird | 17.04 zesty | Fixed 1:52.1.1+build1-0ubuntu0.17.04.1 |
| 16.10 yakkety | Fixed 1:52.1.1+build1-0ubuntu0.16.10.1 |
| 16.04 LTS xenial | Fixed 1:52.1.1+build1-0ubuntu0.16.04.1 |
| 14.04 LTS trusty | Fixed 1:52.1.1+build1-0ubuntu0.14.04.1 |

---

* [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-2016-10195?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 |
| --- | --- |
| libevent | * Upstream:   [96f64a0](https://github.com/libevent/libevent/commit/96f64a022014a208105ead6c8a7066018449d86d) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-10195)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-10195)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-10195)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-10195)

### Related Ubuntu Security Notices (USN)

+ [USN-3278-1](https://usn.ubuntu.com/USN-3278-1)
+ Thunderbird vulnerabilities
+ 16 May 2017

+ [USN-3228-1](https://usn.ubuntu.com/USN-3228-1)
+ libevent vulnerabilities
+ 13 March 2017

### Other references

* <http://www.openwall.com/lists/oss-security/2017/01/31/17>
* <https://www.mozilla.org/en-US/security/advisories/mfsa2017-10/>
* <https://www.mozilla.org/en-US/security/advisories/mfsa2017-13/>
* <https://www.cve.org/CVERecord?id=CVE-2016-10195>