What’s Vulnerable › Vulnerabilities

CVE-2020-8167: CSRF Vulnerability in rails-ujs

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-06-19 · updated 2026-06-17
• Weakness: CWE-352

Description

A CSRF vulnerability exists in rails <= 6.0.3 rails-ujs module that could allow attackers to send CSRF tokens to wrong domains.

Affected products

• Debian Linux: 10.0
• Ruby on Rails: before 5.2.4.3; from 6.0.0 before 6.0.3.1 — fixed in 5.2.4.3, 6.0.3.1
• Rubygems Actionview: from 5.0.0 before 5.2.4.3; from 6.0.0 before 6.0.3.1; 5.0.0, 5.0.0.1, 5.0.1, 5.0.1.rc1, 5.0.1.rc2, 5.0.2 (+59) — fixed in 5.2.4.3, 6.0.3.1

How to fix

Upgrade to a fixed version: Ruby on Rails 5.2.4.3, 6.0.3.1; Rubygems Actionview 5.2.4.3, 6.0.3.1. Check the vendor advisory for mitigations.

References

• https://groups.google.com/g/rubyonrails-security/c/x9DixQDG9a0
• https://hackerone.com/reports/189878
• https://www.debian.org/security/2020/dsa-4766
• https://groups.google.com/g/rubyonrails-security/c/x9DixQDG9a0
• https://hackerone.com/reports/189878
• https://www.debian.org/security/2020/dsa-4766

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