CVE-2021-22881

MEDIUM
6.1
CVSS Score
Published: February 11, 2021 at 04:12 PM UTC
Updated: June 17, 2026 at 03:37 AM UTC
2 products affected across 2 vendorsFedoraRails

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Severity
MEDIUM6.1
Exploit prediction
EPSS 87%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

6.0.0 ≤ v < 6.0.3.56.1.0 ≤ v < 6.1.2.1
Affected range stops below 6.0.3.5, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 6.1.2.1 (unaffected)

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-601

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