--- title: CVE-2023-6209 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-2023-6209 --- # CVE-2023-6209 Publication date 21 November 2023 Last updated 26 August 2025 --- Ubuntu priority **Medium** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **6.5 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2023-6209#impact-score) Toggle side navigation ## Description Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5. [Read the notes from the security team](https://ubuntu.com/security/CVE-2023-6209#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 120.0+build2-0ubuntu0.20.04.1 | | 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 | Fixed 1:115.5.0+build1-0ubuntu1 | | 23.10 mantic | Fixed 1:115.5.0+build1-0ubuntu0.23.10.1 | | 23.04 lunar | Fixed 1:115.5.0+build1-0ubuntu0.23.04.1 | | 22.04 LTS jammy | Fixed 1:115.5.0+build1-0ubuntu0.22.04.1 | | 20.04 LTS focal | Fixed 1:115.5.0+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 | --- * [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** 6.5 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | Low | | Privileges required | None | | User interaction | Required | | Scope | Unchanged | | Confidentiality impact | High | | Integrity impact | None | | Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 6.5 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-6209) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-6209) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2023-6209) * [Debian](https://security-tracker.debian.org/tracker/CVE-2023-6209) ### Related Ubuntu Security Notices (USN) + [USN-6509-1](https://usn.ubuntu.com/USN-6509-1) + Firefox vulnerabilities + 23 November 2023 + [USN-6515-1](https://usn.ubuntu.com/USN-6515-1) + Thunderbird vulnerabilities + 27 November 2023 ### Other references * * * * * * * *