CVE-2020-8184 Rack allows Percent-encoded cookies to overwrite existing prefixed cookie names

What is CVE-2020-8184?

CVE-2020-8184 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 19 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A reliance on cookies without validation/integrity check security vulnerability exists in rack < 2.2.3, rack < 2.1.4 that makes it is possible for an attacker to forge a secure or host-only cookie prefix.

Weakness: CWE-20, CWE-784

Which versions are affected by CVE-2020-8184?

4 open source packages ship an affected version, including rack. It affects 3 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Rack Project Rack.

How do I fix CVE-2020-8184?

Upgrade rack to a fixed version for your release line: 2.1.4 or 2.2.3.

Is CVE-2020-8184 being exploited?

There is no known exploitation of CVE-2020-8184 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-2020-8184, GHSA-j6w9-fv6q-3q52, MGASA-2020-0306, UBUNTU-CVE-2020-8184.