--- title: "CVE-2018-12399\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-2018-12399?format=md keywords: index, follow --- # CVE-2018-12399 Publication date 24 October 2018 Last updated 25 August 2025 --- Ubuntu priority **Low** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **4.3 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2018-12399?format=md#impact-score) Toggle side navigation ## Description When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. This vulnerability affects Firefox < 63. [Read the notes from the security team](https://ubuntu.com/security/CVE-2018-12399?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | firefox | 24.04 LTS noble | Fixed 63.0+build1-0ubuntu1 | | 23.10 mantic | Fixed 63.0+build1-0ubuntu1 | | 23.04 lunar | Fixed 63.0+build1-0ubuntu1 | | 22.10 kinetic | Fixed 63.0+build1-0ubuntu1 | | 22.04 LTS jammy | Fixed 63.0+build1-0ubuntu1 | | 21.10 impish | Fixed 63.0+build1-0ubuntu1 | | 21.04 hirsute | Fixed 63.0+build1-0ubuntu1 | | 20.10 groovy | Fixed 63.0+build1-0ubuntu1 | | 20.04 LTS focal | Fixed 63.0+build1-0ubuntu1 | | 19.10 eoan | Fixed 63.0+build1-0ubuntu1 | | 19.04 disco | Fixed 63.0+build1-0ubuntu1 | | 18.10 cosmic | Fixed 63.0+build2-0ubuntu0.18.10.2 | | 18.04 LTS bionic | Fixed 63.0+build2-0ubuntu0.18.04.2 | | 16.04 LTS xenial | Fixed 63.0+build2-0ubuntu0.16.04.2 | | 14.04 LTS trusty | Fixed 63.0+build2-0ubuntu0.14.04.2 | | mozjs38 | 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 | Not in release | | 21.10 impish | Not in release | | 21.04 hirsute | Not in release | | 20.10 groovy | Not in release | | 20.04 LTS focal | Not in release | | 19.10 eoan | Not in release | | 19.04 disco | Not in release | | 18.10 cosmic | 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 | | 22.10 kinetic | Not in release | | 22.04 LTS jammy | Not in release | | 21.10 impish | Not in release | | 21.04 hirsute | Not in release | | 20.10 groovy | Ignored end of life | | 20.04 LTS focal | Ignored | | 19.10 eoan | Ignored end of life | | 19.04 disco | Ignored end of life | | 18.10 cosmic | Ignored end of life | | 18.04 LTS bionic | Ignored | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | | mozjs60 | 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 | Not in release | | 21.10 impish | Not in release | | 21.04 hirsute | Not in release | | 20.10 groovy | Not in release | | 20.04 LTS focal | Not in release | | 19.10 eoan | Ignored end of life | | 19.04 disco | Ignored end of life | | 18.10 cosmic | Ignored end of life | | 18.04 LTS bionic | Not in release | | 16.04 LTS xenial | Not in release | | 14.04 LTS trusty | Not in release | --- * [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 ## Severity score breakdown CVSS version: CVSS v3.0 **Base score** 4.3 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | Low | | Privileges required | None | | User interaction | Required | | Scope | Unchanged | | Confidentiality impact | None | | Integrity impact | Low | | Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 4.3 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-12399) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-12399) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-12399) * [Debian](https://security-tracker.debian.org/tracker/CVE-2018-12399) ### Related Ubuntu Security Notices (USN) + [USN-3801-1](https://usn.ubuntu.com/USN-3801-1) + Firefox vulnerabilities + 24 October 2018 ### Other references * *