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TI-2026-60037 Aliases CVE-2026-88011GHSA-rf44-j88r-hh8c

Traefik: ForwardAuth identity spoofing via dot-form header alias

Priority LOW 26CWE-290Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-290.

Summary

Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.56, and from 3.0.0 until 3.7.12, a client-supplied dot-form header such as X.Authenticated.User survives ForwardAuth replacement and underscoreHeadersStrategy because Go treats it as distinct from X-Authenticated-User while normalization-prone CGI, WSGI, PHP, and NGINX backends collapse both names. A backend can consequently consume the client value instead of the identity Traefik asserted, allowing identity spoofing for any header managed by Traefik. The aliasHeadersStrategy protection is disabled by default and must be configured as delete or reject. The mitigation is available in 2.11.56 and 3.7.12.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0042 36th percentileScored 2026-11-07
Fix Fixed traefik (traefik): 2.11.56, 3.7.12github.com/traefik/traefik/v2 (Go): 2.11.56+1 more productRed Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
traefiktraefikbefore 2.11.56; 3.0.0 to before 3.7.122.11.56, 3.7.12Patch availableCNA
—github.com/traefik/traefik/v2 (Go)before 2.11.562.11.56Patch availableGHSA-rf44-j88r-hh8c
—github.com/traefik/traefik/v3 (Go)3.0.0 to before 3.7.123.7.12Patch availableGHSA-rf44-j88r-hh8c
  • traefik Vendortraefik Affected before 2.11.56; 3.0.0 to before 3.7.12 Fixed in 2.11.56, 3.7.12 Patch available CNA
  • github.com/traefik/traefik/v2 (Go) Vendor— Affected before 2.11.56 Fixed in 2.11.56 Patch available GHSA-rf44-j88r-hh8c
  • github.com/traefik/traefik/v3 (Go) Vendor— Affected 3.0.0 to before 3.7.12 Fixed in 3.7.12 Patch available GHSA-rf44-j88r-hh8c

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*before 2.11.56; 3.0.0 to before 3.7.12Vulnerabletraefik
  • cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* Versions before 2.11.56; 3.0.0 to before 3.7.12 Vulnerable ·traefik

Remediation

  • Fix · CNA traefik (traefik) Fixed in 2.11.56, 3.7.12
  • Fix · GHSA-rf44-j88r-hh8c github.com/traefik/traefik/v2 (Go) Fixed in 2.11.56 Advisory →
  • Fix · GHSA-rf44-j88r-hh8c github.com/traefik/traefik/v3 (Go) Fixed in 3.7.12 Advisory →

Red Hat 1 advisory

  • RHSA-2026:90321 Released 2026-10-26 · Red Hat rating Critical
    Red Hat OpenShift Dev Spaces 3.31.0 Release.
    • Red Hat OpenShift Dev Spaces 3.31 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/jetbrains-ide-rhel9 +8

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat OpenShift Dev Spaces 3.31Fixed RHSA-2026:90321
Not affected: 1 product
  • Red Hat OpenShift Dev Spaces 3.31

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-88011
  2. 2026-10-03 Alias added: GHSA-rf44-j88r-hh8c
  3. 2026-10-29 Fix available: Red Hat OpenShift Dev Spaces 3.31 · Red Hat
  4. 2026-10-30 Fix available: RHSA-2026:90321 · Red Hat

References

Patch 3

Advisory 1

Other 3

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2023-25774 Uncontrolled Resource Consumption in Traefik CVSS 3.1HIGH 7.5
  • TI-2025-40914 Traefik doesn't Prevent Path Normalization Bypass in Router + Middleware Rules CVSS 4.0MEDIUM 6.9
  • TI-2022-07529 Authorization header displayed in the debug logs CVSS 3.1MEDIUM 6.5
  • TI-2024-30459 HTTP client can remove the X-Forwarded headers in Traefik CVSS 3.1CRITICAL 9.8
  • TI-2026-60261 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect CVSS 4.0CRITICAL 9.3
See all 83 →

Sources

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