---
title: "CVE-2023-26554\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-2023-26554?format=md
keywords: index, follow
---

# CVE-2023-26554

Publication date 11 April 2023

Last updated 26 August 2025

---

Ubuntu priority

**Negligible**

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

## Cvss 3 Severity Score

**5.6 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2023-26554?format=md#impact-score)

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## Description

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when
adding a '\0' character. An adversary may be able to attack a client ntpq
process, but cannot attack ntpd.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2023-26554?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| ntp | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release |
| 25.04 plucky | Not in release |
| 24.10 oracular | Not in release |
| 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Needs evaluation |
| 20.04 LTS focal | Needs evaluation |
| 18.04 LTS bionic | Needs evaluation |
| 16.04 LTS xenial | Needs evaluation |
| 14.04 LTS trusty | Needs evaluation |

---

* [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

---

### [rodrigo-zaiden](https://launchpad.net/~rodrigo-zaiden)

ntpq CLI issue only.

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.6 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.6 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-26554)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-26554)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2023-26554)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2023-26554)

### Other references

* <https://github.com/spwpun/ntp-4.2.8p15-cves/blob/main/CVE-2023-26554>
* <https://github.com/spwpun/ntp-4.2.8p15-cves/issues/1#issuecomment-1506667321>
* <https://www.cve.org/CVERecord?id=CVE-2023-26554>