--- title: "CVE-2018-18506\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-2018-18506?format=md keywords: index, follow --- # CVE-2018-18506 Publication date 30 January 2019 Last updated 25 August 2025 --- Ubuntu priority **Medium** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) ## Cvss 3 Severity Score **5.9 · Medium** [Score breakdown](https://ubuntu.com/security/CVE-2018-18506?format=md#impact-score) Toggle side navigation ## Description When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65. [Read the notes from the security team](https://ubuntu.com/security/CVE-2018-18506?format=md#notes) ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | firefox | 24.04 LTS noble | Fixed 65.0+build2-0ubuntu1 | | 23.10 mantic | Fixed 65.0+build2-0ubuntu1 | | 23.04 lunar | Fixed 65.0+build2-0ubuntu1 | | 22.10 kinetic | Fixed 65.0+build2-0ubuntu1 | | 22.04 LTS jammy | Fixed 65.0+build2-0ubuntu1 | | 21.10 impish | Fixed 65.0+build2-0ubuntu1 | | 21.04 hirsute | Fixed 65.0+build2-0ubuntu1 | | 20.10 groovy | Fixed 65.0+build2-0ubuntu1 | | 20.04 LTS focal | Fixed 65.0+build2-0ubuntu1 | | 19.10 eoan | Fixed 65.0+build2-0ubuntu1 | | 19.04 disco | Fixed 65.0+build2-0ubuntu1 | | 18.10 cosmic | Fixed 65.0+build2-0ubuntu0.18.10.1 | | 18.04 LTS bionic | Fixed 65.0+build2-0ubuntu0.18.04.1 | | 16.04 LTS xenial | Fixed 65.0+build2-0ubuntu0.16.04.1 | | 14.04 LTS trusty | Fixed 65.0+build2-0ubuntu0.14.04.1 | | 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 | | thunderbird | 24.04 LTS noble | Fixed 60.6.1+build2-0ubuntu1 | | 23.10 mantic | Fixed 60.6.1+build2-0ubuntu1 | | 23.04 lunar | Fixed 60.6.1+build2-0ubuntu1 | | 22.10 kinetic | Fixed 60.6.1+build2-0ubuntu1 | | 22.04 LTS jammy | Fixed 60.6.1+build2-0ubuntu1 | | 21.10 impish | Fixed 60.6.1+build2-0ubuntu1 | | 21.04 hirsute | Fixed 60.6.1+build2-0ubuntu1 | | 20.10 groovy | Fixed 60.6.1+build2-0ubuntu1 | | 20.04 LTS focal | Fixed 60.6.1+build2-0ubuntu1 | | 19.10 eoan | Fixed 60.6.1+build2-0ubuntu1 | | 19.04 disco | Fixed 60.6.1+build2-0ubuntu1 | | 18.10 cosmic | Fixed 1:60.6.1+build2-0ubuntu0.18.10.1 | | 18.04 LTS bionic | Fixed 1:60.6.1+build2-0ubuntu0.18.04.1 | | 16.04 LTS xenial | Fixed 1:60.6.1+build2-0ubuntu0.16.04.1 | | 14.04 LTS trusty | Fixed 1:60.6.1+build2-0ubuntu0.14.04.1 | --- * [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** 5.9 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | High | | Privileges required | None | | User interaction | None | | Scope | Unchanged | | Confidentiality impact | None | | Integrity impact | High | | Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 5.9 · Medium | | Exploitability score | - | | Impact score | - | **Vector:** CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-18506) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2018-18506) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2018-18506) * [Debian](https://security-tracker.debian.org/tracker/CVE-2018-18506) ### Related Ubuntu Security Notices (USN) + [USN-3927-1](https://usn.ubuntu.com/USN-3927-1) + Thunderbird vulnerabilities + 28 March 2019 + [USN-3874-1](https://usn.ubuntu.com/USN-3874-1) + Firefox vulnerabilities + 30 January 2019 ### Other references * * *