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GO-2026-6209 CVE-2026-71327 GHSA-fgjj-px3w-67xx

Traefik: Gateway API route identity collision allows cross-namespace backend hijacking in github.com/traefik/traefik

High Go
Severity
7.6 / 10
High · CVSS 4.0
Exploit chance (EPSS)
0.48%
Chance of exploitation in the next 30 days. Higher than 41.49% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-694 Use of Multiple Resources with Duplicate Identifier
Fix
3.6.25
Upgrade github.com/traefik/traefik/v3 to this version or later

Description

Traefik: Gateway API route identity collision allows cross-namespace backend hijacking in github.com/traefik/traefik

Affected versions

Go

PackageVulnerableFixed in
github.com/traefik/traefik
all versions
No fix yet
github.com/traefik/traefik/v2
all versions
No fix yet
github.com/traefik/traefik/v3
>= 3.0.0, < 3.6.25
3.6.25
github.com/traefik/traefik/v3
>= 3.7.0, < 3.7.10
3.7.10
github.com/traefik/traefik/v3
>= 3.0.0, < 3.6.25
>= 3.7.0, < 3.7.10
3.6.25
3.7.10

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

github.com/traefik/traefik/v3 Go → 3.6.25

go
go get github.com/traefik/traefik/v3@v3.6.25 && go mod tidy

Severity breakdown

CVSS 4.0 7.6

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack vector
Network
Attack complexity
Low
Attack requirements
Present
Privileges required
Low
User interaction
None
Confidentiality (vulnerable system)
High
Integrity (vulnerable system)
High
Availability (vulnerable system)
None
Confidentiality (subsequent systems)
None
Integrity (subsequent systems)
None
Availability (subsequent systems)
None
Exploit maturity
Not defined
Scope
X

CVSS 3.1 8.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Weakness

CWE-694: Use of Multiple Resources with Duplicate Identifier

The product uses multiple resources that can have the same identifier, in a context in which unique identifiers are required.

How to prevent it
  • Architecture and Design: Where possible, use unique identifiers. If non-unique identifiers are detected, then do not operate any resource with a non-unique identifier and report the error appropriately.

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GO-2026-6558
Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle
Medium Also affects github.com/traefik/traefik
GHSA-f52w-8j3h-j724
Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging
High Also affects github.com/traefik/traefik
GHSA-w4v4-9rw7-5326
Traefik: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') and Incorrect Authorization
Critical Also affects github.com/traefik/traefik
GHSA-qqjf-53cj-pwvv
Traefik HTTP/3 Backend NTLM Connection Reuse
Critical Also affects github.com/traefik/traefik
GO-2026-6467
Traefik entrypoint header-name sanitization bypassed via request trailers
High Also affects github.com/traefik/traefik
GHSA-rf44-j88r-hh8c
Traefik: ForwardAuth identity spoofing via dot-form header alias
High Also affects github.com/traefik/traefik
GHSA-7ghq-v6jf-g56c
Traefik: respondingTimeouts.readTimeout is not applied to HTTP/3, leaving slow-body uploads unbounded
Medium Also affects github.com/traefik/traefik
GHSA-62fc-8686-hfmq
Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef
Medium Also affects github.com/traefik/traefik
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