CVE-2026-65600
Traefik versions <= v2.11.51, >= v3.6.0 <= v3.6.22, and >= v3.7.0 <= v3.7.6 contain an authentication bypass via path traversal in the ReplacePathRegex middlew…
Impact
Traefik versions <= v2.11.51, >= v3.6.0 <= v3.6.22, and >= v3.7.0 <= v3.7.6 contain an authentication bypass via path traversal in the ReplacePathRegex middleware. When ReplacePathRegex is configured with a regex that captures user-controlled path segments without a mandatory path separator (e.g. regex "^/api(.*)", replacement "/$1"), the middleware forwards the replaced path to the backend without validating that it matches its normalized form. An unauthenticated remote attacker can send a crafted request (e.g. GET /api../admin) that produces an un-normalized path such as /../admin, which a backend that normalizes paths resolves to a protected route, bypassing authentication middleware. Fixed in v2.11.52, v3.6.23, and v3.7.7.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/traefik/traefik/v2 | <= 2.11.51 | 2.11.52 |
| go | github.com/traefik/traefik/v3 | <= 3.6.22 | 3.6.23 |
| go | github.com/traefik/traefik | <= 1.7.34 | none recorded |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Traefik | Traefik | before 2.11.52 from 3.6.0 before 3.6.23 from 3.7.0 before 3.7.7 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-cxjq-mrr5-89rv
- https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv
- https://nvd.nist.gov/vuln/detail/CVE-2026-65600
- https://github.com/traefik/traefik/commit/3f10dd442479530560f010167cac2947676d9b29
- https://github.com/traefik/traefik/releases/tag/v2.11.52
- https://github.com/traefik/traefik/releases/tag/v3.6.23
- https://github.com/traefik/traefik/releases/tag/v3.7.7
- https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex