---
title: "CVE-2025-49809\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-2025-49809?format=md
keywords: index, follow
---

# CVE-2025-49809

Publication date 4 July 2025

Last updated 16 July 2026

---

Ubuntu priority

**Low**

[Why this priority?](https://ubuntu.com/security/CVE-2025-49809?format=md#priority-reason )

## Cvss 3 Severity Score

**7.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2025-49809?format=md#impact-score)

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## Description

mtr through 0.95, in certain privileged contexts, mishandles execution of a
program specified by the MTR\_PACKET environment variable. NOTE: mtr on
macOS may often have Sudo rules, as an indirect consequence of Homebrew not
installing setuid binaries.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2025-49809?format=md#notes)

### Why is this CVE low priority?

Requires bad sudo configuration

[Learn more about Ubuntu priority](https://ubuntu.com/security/cves/about#priority)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| mtr | 26.04 LTS resolute | Needs evaluation |
| 25.10 questing | Ignored end of life, was needs-triage |
| 25.04 plucky | Ignored end of life, was needs-triage |
| 24.10 oracular | Ignored end of life, was needs-triage |
| 24.04 LTS noble | Needs evaluation |
| 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)
* [Patch details](https://ubuntu.com/security/CVE-2025-49809?format=md#patch-details)

## Notes

---

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

introduced in 0.88 by:
https://github.com/traviscross/mtr/commit/fcda9e8b82ca354049fa0ee9cfcb2eaaae623ee0
This issue only affects deployments where an unprivileged user
can only run mtr though a specialized sudo configuration. While
this is a common scenario on macOS, it is unlikely to be a
common scenario on Ubuntu.
The patch allows creating a file called
/etc/mtr.is.run.under.sudo to disable the MTR\_PACKET environment
variable from being used, so the patch alone will not fix
existing sudo configurations.
In addition, the default Ubuntu sudoers file already resets the
environment with the env\_reset option, so this is unlikely to be
an issue in practice. Marking priority as low.

### 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 |
| --- | --- |
| mtr | * Upstream:   [5226f10](https://github.com/traviscross/mtr/commit/5226f105f087c29d3cfad9f28000e7536af91ac6) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.8 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.8 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-49809)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2025-49809)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2025-49809)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2025-49809)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2025-49809>
* <https://github.com/traviscross/mtr/blob/master/SECURITY>