---
title: "CVE-2023-6873\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-2023-6873?format=md
keywords: index, follow
---

# CVE-2023-6873

Publication date 20 December 2023

Last updated 26 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**8.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2023-6873?format=md#impact-score)

Toggle side navigation

## Description

Memory safety bugs present in Firefox 120. Some of these bugs showed
evidence of memory corruption and we presume that with enough effort some
of these could have been exploited to run arbitrary code. This
vulnerability affects Firefox < 121.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2023-6873?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| firefox | 24.04 LTS noble | Not affected |
| 23.10 mantic | Not affected |
| 23.04 lunar | Ignored end of life, was needs-triage |
| 22.04 LTS jammy | Not affected |
| 20.04 LTS focal | Fixed 121.0+build1-0ubuntu0.20.04.1 |
| 18.04 LTS bionic | Ignored end of standard support |
| 16.04 LTS xenial | Ignored end of standard support |
| 14.04 LTS trusty | Ignored end of standard support |
| mozjs102 | 24.04 LTS noble | Ignored |
| 23.10 mantic | Ignored end of life, was needs-triage |
| 23.04 lunar | Ignored end of life, was needs-triage |
| 22.04 LTS jammy | Ignored |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| mozjs38 | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.04 LTS jammy | Not in release |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Ignored |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| mozjs52 | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.04 LTS jammy | Not in release |
| 20.04 LTS focal | Ignored |
| 18.04 LTS bionic | Ignored |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| mozjs68 | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.04 LTS jammy | Not in release |
| 20.04 LTS focal | Ignored |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| mozjs78 | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Ignored end of life, was needs-triage |
| 22.04 LTS jammy | Ignored |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| mozjs91 | 24.04 LTS noble | Not in release |
| 23.10 mantic | Not in release |
| 23.04 lunar | Not in release |
| 22.04 LTS jammy | Ignored |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| thunderbird | 24.04 LTS noble | Not affected |
| 23.10 mantic | Not affected |
| 23.04 lunar | Ignored end of life, was needed |
| 22.04 LTS jammy | Not affected |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Ignored end of standard support |
| 16.04 LTS xenial | Ignored end of standard support |
| 14.04 LTS trusty | Ignored end of standard support |

---

* [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

---

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

mozjs contains a copy of the SpiderMonkey JavaScript engine

---

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

starting with Ubuntu 22.04, the firefox package is just a script
that installs the Firefox snap

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

8.8 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 8.8 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-6873)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-6873)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2023-6873)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2023-6873)

### Related Ubuntu Security Notices (USN)

+ [USN-6562-1](https://usn.ubuntu.com/USN-6562-1)
+ Firefox vulnerabilities
+ 2 January 2024

### Other references

* <https://www.mozilla.org/en-US/security/advisories/mfsa2023-56/#CVE-2023-6873>
* <https://www.mozilla.org/en-US/security/advisories/mfsa2023-55/#CVE-2023-6873>
* <https://bugzilla.mozilla.org/buglist.cgi?bug_id=1855327%2C1862089%2C1862723>
* <https://www.mozilla.org/security/advisories/mfsa2023-56/>
* <https://www.cve.org/CVERecord?id=CVE-2023-6873>
