---
title: "CVE-2015-1798\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-2015-1798?format=md
keywords: index, follow
---

# CVE-2015-1798

Publication date 8 April 2015

Last updated 24 July 2024

---

Ubuntu priority

**Medium**

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

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## Description

The symmetric-key feature in the receive function in ntp\_proto.c in ntpd in
NTP 4.x before 4.2.8p2 requires a correct MAC only if the MAC field has a
nonzero length, which makes it easier for man-in-the-middle attackers to
spoof packets by omitting the MAC.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2015-1798?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| ntp | 14.10 utopic | Fixed 1:4.2.6.p5+dfsg-3ubuntu2.14.10.3 |
| 14.04 LTS trusty | Fixed 1:4.2.6.p5+dfsg-3ubuntu2.14.04.3 |
| 12.04 LTS precise | Fixed 1:4.2.6.p3+dfsg-1ubuntu3.4 |
| 10.04 LTS lucid | 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-2015-1798?format=md#patch-details)

## Notes

---

### [mdeslaur](https://launchpad.net/~mdeslaur)

4.2.5p99+ only

### 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 |
| --- | --- |
| ntp | * Upstream:   <http://bk.ntp.org/ntp-stable/?PAGE=patch&REV=550a80b0iGyIv4t9J1GJ_74V_eEx4A> |

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1798)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-1798)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-1798)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-1798)

### Related Ubuntu Security Notices (USN)

+ [USN-2567-1](https://usn.ubuntu.com/USN-2567-1)
+ NTP vulnerabilities
+ 13 April 2015

### Other references

* <http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities>
* <https://www.cve.org/CVERecord?id=CVE-2015-1798>