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TI-2021-05742 Aliases CVE-2021-22881GHSA-8877-prq4-9xfw

Open redirect in https://github.com/rails/rails

Priority HIGH 69CWE-601Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Spoofing
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-601.

Summary

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.

Why it matters now

EPSS 0.87301 99th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix Partial actionpack (RubyGems): 6.0.3.5, 6.1.2.1Red Hat: 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—https://github.com/rails/railsFixed in 6.1.2.1, 6.0.3.5—No fix listedCNA
—actionpack (RubyGems)6.0.0 to before 6.0.3.56.0.3.5Patch availableGHSA-8877-prq4-9xfw
—actionpack (RubyGems)6.1.0 to before 6.1.2.16.1.2.1Patch availableGHSA-8877-prq4-9xfw
  • https://github.com/rails/rails Vendor— Affected Fixed in 6.1.2.1, 6.0.3.5 Fixed in — No fix listed CNA
  • actionpack (RubyGems) Vendor— Affected 6.0.0 to before 6.0.3.5 Fixed in 6.0.3.5 Patch available GHSA-8877-prq4-9xfw
  • actionpack (RubyGems) Vendor— Affected 6.1.0 to before 6.1.2.1 Fixed in 6.1.2.1 Patch available GHSA-8877-prq4-9xfw

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*6.0.0 to before 6.0.3.5; 6.1.0 to before 6.1.2.1VulnerableRails
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
  • cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:* Versions 6.0.0 to before 6.0.3.5; 6.1.0 to before 6.1.2.1 Vulnerable ·Rails
  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject

Remediation

  • Fix · GHSA-8877-prq4-9xfw actionpack (RubyGems) Fixed in 6.0.3.5 Advisory →
  • Fix · GHSA-8877-prq4-9xfw actionpack (RubyGems) Fixed in 6.1.2.1 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    https://github.com/rails/rails — FEDORA-2021-b571fca1b8

    2 records Highest priority Priority HIGH 1 HIGH, 1 MEDIUM

    Other records, highest priority first

    • TI-2021-05741 Uncontrolled resource consumption in https://github.com/rails/railsPriority MEDIUM 40
    Show all 2 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
CloudForms Management Engine 5AffectedNo fix planned: Will not fix
Not affected: 1 product
  • Red Hat Satellite 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-22881
  2. 2026-10-03 Alias added: GHSA-8877-prq4-9xfw

References

Exploit 2

Patch 2

Advisory 4

Other 8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences