CVE-2026-48020
Traefik has a StripPrefix Route-Level Auth Bypass via Path Normalization
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/traefik/traefik/v2 | < 2.11.48 | 2.11.48 |
| go | github.com/traefik/traefik/v3 | < 3.6.19 | 3.6.19 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Traefik | Traefik | before 2.11.48 from 3.0.0 before 3.6.19 from 3.7.0 before 3.7.3 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-xf64-8mw2-4gr2
- 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://nvd.nist.gov/vuln/detail/CVE-2026-48020
- 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