CVE-2018-12395

HighCVSS 7.5/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.0 7.5/10CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected software

Vendor	Product	Versions
Mozilla	Firefox ESR	>= unspecified, < 60.3
Mozilla	Firefox	>= unspecified, < 63

References

http://www.securityfocus.com/bid/105718Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041944Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2018:3005Third Party Advisory
https://access.redhat.com/errata/RHSA-2018:3006Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1467523Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2018/11/msg00008.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201811-04Third Party Advisory
https://usn.ubuntu.com/3801-1/Third Party Advisory
https://www.debian.org/security/2018/dsa-4324Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-26/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2018-27/Vendor Advisory
http://www.securityfocus.com/bid/105718Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041944Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2018:3005Third Party Advisory
https://access.redhat.com/errata/RHSA-2018:3006Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1467523Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2018/11/msg00008.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201811-04Third Party Advisory
https://usn.ubuntu.com/3801-1/Third Party Advisory
https://www.debian.org/security/2018/dsa-4324Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2018-26/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2018-27/Vendor Advisory

Timeline

Published: Feb 28, 2019
Last modified: Jun 17, 2026
NVD status: Modified

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