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TI-2026-85133 Aliases CVE-2026-63183

Host header injection in OmniAuth callback URLs

Priority LOW 30CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-346.

Summary

OmniAuth before 2.2.0 builds provider callback URLs from request host information when no fixed full_host or framework host validation is configured. A remote unauthenticated client can send a forged Host header, causing host header injection in applications whose web framework does not verify incoming host headers. Applications using appropriately configured Rails host authorization or a fixed full_host are not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

OmniAuth is a flexible authentication system utilizing Rack middleware. Prior to 2.2.0, OmniAuth derives provider callback URLs from request-controlled host information when neither a fixed full_host nor framework-level incoming host validation is configured. A remote unauthenticated client can supply a forged Host header, creating a host header injection risk in applications whose web framework does not verify incoming host headers. Applications using appropriately configured Rails host authorization or a fixed full_host are not affected by this path. This issue is fixed in version 2.2.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00181 7th percentileScored 2026-11-07
Fix Fixed omniauth (omniauth): 2.2.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OmniAuthomniauthbefore 2.2.02.2.0Patch availableCNA
  • omniauth VendorOmniAuth Affected before 2.2.0 Fixed in 2.2.0 Patch available CNA

Remediation

OmniAuth is fixed in version 2.2.0.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA omniauth (omniauth) Fixed in 2.2.0

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-11-04 Threatist record created from CVE-2026-63183
  2. 2026-11-05 CISA SSVC decision points changed
  3. 2026-11-05 Priority changed: MEDIUM → LOW
  4. 2026-11-06 Affected versions changed · Red Hat
  5. 2026-11-06 CVSS score added · Red Hat

References

Other 2

  • TI-2025-18946 Ruby SAML vulnerable to SAML authentication bypass due to namespace handling (parser differential) CVSS 4.0CRITICAL 9.3
  • TI-2024-30458 The Ruby SAML library vulnerable to a SAML authentication bypass via Incorrect XPath selector CVSS 3.1CRITICAL 10.0
  • TI-2025-18945 ruby-saml vulnerable to SAML authentication bypass due to DOCTYPE handling (parser differential) CVSS 4.0CRITICAL 9.3
  • TI-2017-08455 Multiple SAML libraries may allow authentication bypass via incorrect XML canonicalization and DOM traversal CVSS 3.0CRITICAL 9.8
  • TI-2020-18798 lib/omniauth/failure_endpoint.rb in OmniAuth before 1.9.2 (and before 2.0) does not escape the message_key value. CVSS 3.1CRITICAL 9.8
  • TI-2025-18947 ruby-saml vulnerable to Remote Denial of Service (DoS) with compressed SAML responses CVSS 4.0HIGH 7.7
See all 8 →

Sources

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