Traefik StripPrefix Route-Level Auth Bypass via Path Normalization (traefik traefik)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.78 % · percentile 56 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Modified
Description
Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.48, 3.6.19, and 3.7.3, there is a high severity vulnerability in Traefik's StripPrefix middleware that allows an unauthenticated attacker to bypass route-level authentication and authorization. When a public router matches on a PathPrefix rule and applies the StripPrefix middleware, a request path containing .. or its percent-encoded form %2e%2e can match the public route at routing time and then, after the prefix is stripped and the path is normalized, resolve to a path served by a separate, authenticated router. As a result, an attacker can reach protected backend paths — such as admin or internal configuration endpoints — without satisfying the authentication middleware attached to the protected router. This vulnerability is fixed in 2.11.48, 3.6.19, and 3.7.3.
Weaknesses (CWE)
- CWE-288 — Authentication Bypass Using an Alternate Path or Channel
- CWE-22 — Improper Limitation of a Pathname to a Restricted Directory
References
- https://github.com/traefik/traefik/security/advisories/GHSA-xf64-8mw2-4gr2
- https://github.com/traefik/traefik/releases/tag/v2.11.48
- https://github.com/traefik/traefik/releases/tag/v3.6.19
- https://github.com/traefik/traefik/releases/tag/v3.7.3
- https://access.redhat.com/security/cve/CVE-2026-48020
- https://bugzilla.redhat.com/show_bug.cgi?id=2491915
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48020.json
- https://access.redhat.com/errata/RHSA-2026:62260
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | HIGH 7.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N | GitHub_M |
| CVSS 3.1 | CRITICAL 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N | redhat-SADP |
| CVSS 4.0 | HIGH 7.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/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 | CRITICAL 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N | NVD · nvd@nist.gov (Primary) |
| CVSS 3.1 | CRITICAL 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N | NVD · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Secondary) |
Advisories
- GHSA-xf64-8mw2-4gr2 — Traefik has a StripPrefix Route-Level Auth Bypass via Path Normalization
- GO-2026-5752 — Traefik has a StripPrefix Route-Level Auth Bypass via Path Normalization in github.com/traefik/traefik
European references
- ENISA EUVD · EUVD-2026-38574
- GCVE · GCVE-0-2026-48020
CERT-FR advisories
- CERTFR-2026-AVI-0908 — Multiples vulnérabilités dans les produits HPE Aruba Networking · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0690 — Multiples vulnérabilités dans Traefik · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*< 2.11.48cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*≥ 3.0.0 < 3.6.19cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*≥ 3.7.0 < 3.7.3
Affected products
| Product | Versions |
|---|---|
| traefik · traefik | affected >= 3.7.0-ea.1, < 3.7.3 ; affected >= 3.0.0-beta1, < 3.6.19 ; affected < 2.11.48 |
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 |