CVE-2018-18506 Server-side request forgery in Firefox

What is CVE-2018-18506?

CVE-2018-18506 is a medium-severity server-side request forgery vulnerability in Canonical Ubuntu Linux, published on 5 Feb 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.

Which versions are affected by CVE-2018-18506?

It affects 12 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Mozilla Firefox, Opensuse Leap, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop and 6 more.

How do I fix CVE-2018-18506?

Upgrade to a fixed version.

Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.

Is CVE-2018-18506 being exploited?

There is no known exploitation of CVE-2018-18506 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-2018-18506, GHSA-4gc3-hqxg-hgp9, UBUNTU-CVE-2018-18506.