CVE-2018-12395 Security feature bypass in Firefox

What is CVE-2018-12395?

CVE-2018-12395 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 28 Feb 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Which versions are affected by CVE-2018-12395?

It affects 8 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Mozilla Firefox, Mozilla Firefox Esr, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server and 2 more.

How do I fix CVE-2018-12395?

Upgrade to a fixed version.

Is CVE-2018-12395 being exploited?

There is no known exploitation of CVE-2018-12395 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2018-12395, GHSA-vw7x-c78h-8w2r, UBUNTU-CVE-2018-12395.