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TI-2026-60034 Aliases CVE-2026-88008GHSA-w4v4-9rw7-5326

Traefik: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') and Incorrect Authorization

Priority LOW 31CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
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-863.

Summary

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.26 until 2.11.57 and 3.7.13, Traefik forwards a client-supplied Connection header requesting Upgrade, the Upgrade: h2c token, and HTTP2-Settings to a shared backend. If the backend accepts h2c and returns 101 Switching Protocols, Traefik enters a raw tunnel and no longer applies routers, BasicAuth, ForwardAuth, IPAllowList, RateLimit, access logging, metrics, or tracing to later HTTP/2 requests, allowing an unauthenticated request through an unprotected route to reach protected paths on the same backend. This issue is fixed in 2.11.57 and 3.7.13.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00487 42nd percentileScored 2026-11-07
Fix Fixed traefik (traefik): 2.11.57, 3.7.13github.com/traefik/traefik/v3 (Go): 3.7.13+1 more productRed Hat: 1 advisory

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
traefiktraefik2.11.26 to before 2.11.57; 3.4.2 to before 3.7.132.11.57, 3.7.13Patch availableCNA
—github.com/traefik/traefik/v3 (Go)3.4.2 to before 3.7.133.7.13Patch availableGHSA-w4v4-9rw7-5326
—github.com/traefik/traefik/v2 (Go)2.11.26 to before 2.11.572.11.57Patch availableGHSA-w4v4-9rw7-5326
  • traefik Vendortraefik Affected 2.11.26 to before 2.11.57; 3.4.2 to before 3.7.13 Fixed in 2.11.57, 3.7.13 Patch available CNA
  • github.com/traefik/traefik/v3 (Go) Vendor— Affected 3.4.2 to before 3.7.13 Fixed in 3.7.13 Patch available GHSA-w4v4-9rw7-5326
  • github.com/traefik/traefik/v2 (Go) Vendor— Affected 2.11.26 to before 2.11.57 Fixed in 2.11.57 Patch available GHSA-w4v4-9rw7-5326

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*2.11.26 to before 2.11.57; 3.4.2 to before 3.7.13Vulnerabletraefik
  • cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* Versions 2.11.26 to before 2.11.57; 3.4.2 to before 3.7.13 Vulnerable ·traefik

Remediation

  • Fix · CNA traefik (traefik) Fixed in 2.11.57, 3.7.13
  • Fix · GHSA-w4v4-9rw7-5326 github.com/traefik/traefik/v3 (Go) Fixed in 3.7.13 Advisory →
  • Fix · GHSA-w4v4-9rw7-5326 github.com/traefik/traefik/v2 (Go) Fixed in 2.11.57 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-2026-88008
  2. 2026-10-03 Alias added: GHSA-w4v4-9rw7-5326
  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