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vulnerability

Ruby on Rails Ruby on Rails: CVE-2021-22881: URL Redirection to Untrusted Site

Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:N)
Published
Feb 11, 2021
Added
Feb 19, 2021
Modified
May 6, 2026

Description

The Host Authorization middleware in Action Pack before 6.1.2.1, 6.0.3.5 suffers from an open redirect vulnerability. Specially crafted `Host` headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website. Impacted applications will have allowed hosts with a leading dot. When an allowed host contains a leading dot, a specially crafted `Host` header can be used to redirect to a malicious website.

Solution

ruby-on-rails-upgrade-latest

References

    Title
    Rapid7 Labs

    2026 Global Threat Landscape Report

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