CVE-2018-18495

Severity: medium (CVSS 6.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-02-28 · updated 2026-06-17
Weakness: CWE-732

Description

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. This vulnerability affects Firefox < 64.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 18.10
Mozilla Firefox: before 64.0 — fixed in 64.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 64.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/106167
https://bugzilla.mozilla.org/show_bug.cgi?id=1427585
https://usn.ubuntu.com/3844-1/
https://www.mozilla.org/security/advisories/mfsa2018-29/
http://www.securityfocus.com/bid/106167
https://bugzilla.mozilla.org/show_bug.cgi?id=1427585
https://usn.ubuntu.com/3844-1/
https://www.mozilla.org/security/advisories/mfsa2018-29/

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