CVE

CVE-2021-22881

6.1

CVSS

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.

Attack Vector

Privileges Req.

User Interaction

https://github.com/rails/rails

Updated Sep 26, 2026View on NVD →

S4E scanner

mediumProduct Based Web Vulnerabilities~10 seconds

CVE-2021-22881 Scanner

CVE-2021-22881 Scanner - Host Header Injection vulnerability in Ruby on Rails

Used 2.4k times · 3.3k assets checked · domain, subdomain, ipv4

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