CVE-2018-12395

Mozilla: WebExtension bypass of domain restrictions through header rewriting

Loading…

Severity

Moderate

Red Hat Product Security

7.5

CVSS 3.0

Review impact separately from score.

Published · October 23, 2018

Updated · November 22, 2025

Description

By rewriting the Host: request headers using the webRequest API, a WebExtension can bypass domain restrictions through domain fronting. This would allow access to domains that share a host that are otherwise restricted. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.

CVSS score applicability

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation

No mitigation is specified in collected source.

CVSS / CWE

CVSS 3.0 · 7.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CWE-284 · Improper Access Control