CVE-2018-18495: Medium severity Mozilla Firefox vulnerability

Published Dec 11, 2018
·
Updated

Last updated 25 August 2025

Other sources

WebExtension content scripts can be loaded into about: pages in some circumstances, in violation of the permissions granted to extensions. This could allow an extension to interfere with the loading and usage of these pages and use capabilities that were intended to be restricted from extensions.

Affected Software

7 affected componentsFixes available
Mozilla Firefox<64.0
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=18.10
Mozilla Firefox<64
64
debian/firefox
149.0.2-1

Event History

Dec 11, 2018
CVE Published
12:00 AM
Feb 28, 2019
CVE Published
via MITRE·06:00 PM
Data Sourced
via MITRE·06:00 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·10:55 PM
Description
Dec 5, 2025
Data Sourced
via Ubuntu·06:20 PM
RemedyDescriptionSeverityAffected Software
Apr 9, 2026
Data Sourced
via Debian·05:08 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2018-18495?

CVE-2018-18495 is a vulnerability in Mozilla Firefox and Ubuntu Linux that allows WebExtension content scripts to be loaded into about: pages, potentially allowing extensions to interfere with the loading and usage of these pages.

2

What is the severity of CVE-2018-18495?

CVE-2018-18495 has a severity rating of 6.5 (medium).

3

How does CVE-2018-18495 affect Mozilla Firefox?

CVE-2018-18495 affects Mozilla Firefox versions up to 64.0.

4

How does CVE-2018-18495 affect Ubuntu Linux?

CVE-2018-18495 affects Ubuntu Linux versions 14.04, 16.04, 18.04, and 18.10.

5

How can I fix CVE-2018-18495?

To fix CVE-2018-18495, users should update to Mozilla Firefox version 64.0 or higher.

Contact

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