# CVE-2018-5133: firefox: If the "app.support.baseURL" preference is changed by a malicious local program to contain HTML and script content, t...

CVE-2018-5133 is fixed in 4 products on 1 platform, first by firefox 59.0.1+build1-0ubuntu1, released June 11, 2018. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-5133
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0149
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 13, 2018

## Description

If the "app.support.baseURL" preference is changed by a malicious local program to contain HTML and script content, this content is not sanitized. It will be executed if a user loads "chrome://browser/content/preferences/in-content/preferences.xul" directly in a tab and executes a search. This stored preference is also executed whenever an EME video player plugin displays a CDM-disabled message as a notification message. This vulnerability affects Firefox < 59.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 59.0.1+build1-0ubuntu1 | [firefox 59.0.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-59.0.1-build1-0ubuntu1.md) | Jun 11, 2018 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 59.0.1+build1-0ubuntu1 | [firefox-globalmenu 59.0.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-59.0.1-build1-0ubuntu1.md) | Jun 11, 2018 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 59.0.1+build1-0ubuntu1 | [firefox-mozsymbols 59.0.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-59.0.1-build1-0ubuntu1.md) | Jun 11, 2018 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 59.0.1+build1-0ubuntu1 | [firefox-testsuite 59.0.1+build1-0ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-59.0.1-build1-0ubuntu1.md) | Jun 11, 2018 |

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Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo