Traefik: Gateway HTTPRoute backendRef filters can leak backend context across routes sharing a Service:port (traefik traefik)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.35 % · percentile 28 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Traefik is an open source HTTP reverse proxy and load balancer. From v3.7.0 prior to v3.7.6, Traefik's Kubernetes Gateway API provider may resolve two accepted HTTPRoutes that target the same backend Service:port but configure different backendRef filters to the same child service and apply only one route's filter set to all requests reaching that backend. In Gateway deployments where backendRef filters set security-sensitive headers, such as tenant identity, authorization context, or values the backend trusts, an attacker who can create an accepted HTTPRoute sharing the same backend Service:port may cause their route's filter context to be applied to another route's requests, potentially crossing namespace boundaries when a ReferenceGrant permits cross-namespace targeting. This issue is fixed in version v3.7.6.
Weaknesses (CWE)
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | MEDIUM 6.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N | GitHub_M |
| CVSS 4.0 | MEDIUM 6.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/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 | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | HIGH 8.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N | NVD · nvd@nist.gov (Primary) |
Advisories
- GHSA-6p8f-p8j2-rqmv — Traefik: Gateway HTTPRoute backendRef filters can leak backend context across routes sharing a Service:port
- GO-2026-6205 — Traefik: Gateway HTTPRoute backendRef filters can leak backend context across routes sharing a Service:port in github.com/traefik/traefik
European references
- ENISA EUVD · EUVD-2026-41938
- GCVE · GCVE-0-2026-54765
CERT-FR advisories
- CERTFR-2026-AVI-0823 — Multiples vulnérabilités dans Traefik · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*≥ 3.7.0 < 3.7.6
Affected products
| Product | Versions |
|---|---|
| traefik · traefik | affected >= 3.7.0, < 3.7.6 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |