CVE-2018-5142: Medium severity Mozilla Firefox vulnerability

Published Mar 13, 2018
·
Updated

If Media Capture and Streams API permission is requested from documents with "data:" or "blob:" URLs, the permission notifications do not properly display the originating domain. The notification states "Unknown protocol" as the requestee, leading to user confusion about which site is asking for this permission. This vulnerability affects Firefox < 59.

Other sources

If Media Capture and Streams API permission is requested from documents with data: or blob: URLs, the permission notifications do not properly display the originating domain. The notification states "Unknown protocol" as the requestee, leading to user confusion about which site is asking for this permission.

Affected Software

6 affected componentsFixes available
Mozilla Firefox<59.0
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=17.10
Mozilla Firefox<59
59
debian/firefox
147.0.4-1

Event History

Mar 13, 2018
CVE Published
12:00 AM
Jun 11, 2018
CVE Published
via MITRE·09:00 PM
Data Sourced
via MITRE·09:00 PM
DescriptionWeakness
Data Sourced
via NVD·09:29 PM
DescriptionSeverityAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:06 PM
Description
Nov 26, 2025
Data Sourced
via Ubuntu·06:15 PM
RemedyDescriptionSeverityAffected Software
Feb 20, 2026
Data Sourced
via Debian·12:49 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2018-5142?

CVE-2018-5142 is a vulnerability in Mozilla Firefox and Ubuntu Linux that allows requests for Media Capture and Streams API permission from documents with 'data:' or 'blob:' URLs to display the wrong originating domain.

2

Which software products are affected by CVE-2018-5142?

Mozilla Firefox versions up to exclusive 59.0 and Ubuntu Linux versions 14.04, 16.04, and 17.10 are affected by CVE-2018-5142.

3

What is the severity of CVE-2018-5142?

The severity of CVE-2018-5142 is medium, with a CVSS score of 5.3.

4

How can I fix CVE-2018-5142 in Mozilla Firefox?

To fix CVE-2018-5142 in Mozilla Firefox, update to version 59.0 or higher.

5

How can I fix CVE-2018-5142 in Ubuntu Linux?

To fix CVE-2018-5142 in Ubuntu Linux, apply the applicable security patch or update the Firefox package to version 59.0 or higher.

Contact

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